651 results on '"Ramón Martínez-Máñez"'
Search Results
2. β‐Galactosidase‐Triggered Photodynamic Elimination of Senescent Cells with a Boron Dipyrromethene‐Based Photosensitizer
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Jacky C. H. Chu, Blanca Escriche‐Navarro, Junlong Xiong, Alba García‐Fernández, Ramón Martínez‐Máñez, and Dennis K. P. Ng
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boron dipyrromethene ,β‐galactosidase ,photodynamic therapy ,senescent cells ,singlet oxygen ,Science - Abstract
Abstract Senescence is a cellular response having physiological and reparative functions to preserve tissue homeostasis and suppress tumor growth. However, the accumulation of senescent cells would cause deleterious effects that lead to age‐related dysfunctions and cancer progression. Hence, selective detection and elimination of senescent cells are crucial yet remain a challenge. A β‐galactosidase (β‐gal)‐activated boron dipyrromethene (BODIPY)‐based photosensitizer (compound 1) is reported here that can selectively detect and eradicate senescent cells. It contains a galactose moiety connected to a pyridinium BODIPY via a self‐immolative nitrophenylene linker, of which the photoactivity is effectively quenched. Upon interactions with the senescence‐associated β‐gal, it undergoes enzymatic hydrolysis followed by self‐immolation, leading to the release of an activated BODIPY moiety by which the fluorescence emission and singlet oxygen generation are restored. The ability of 1 to detect and eliminate senescent cells is demonstrated in vitro and in vivo, using SK‐Mel‐103 tumor‐bearing mice treated with senescence‐inducing therapy. The results demonstrate that 1 can be selectively activated in senescent cells to trigger a robust senolytic effect upon irradiation. This study breaks new ground in the design and application of new senolytic agents based on photodynamic therapy.
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- 2024
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3. A renal clearable fluorogenic probe for in vivo β-galactosidase activity detection during aging and senolysis
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Sara Rojas-Vázquez, Beatriz Lozano-Torres, Alba García-Fernández, Irene Galiana, Ana Perez-Villalba, Pablo Martí-Rodrigo, M. José Palop, Marcia Domínguez, Mar Orzáez, Félix Sancenón, Juan F. Blandez, Isabel Fariñas, and Ramón Martínez-Máñez
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Science - Abstract
Abstract Accumulation of senescent cells with age leads to tissue dysfunction and related diseases. Their detection in vivo still constitutes a challenge in aging research. We describe the generation of a fluorogenic probe (sulfonic-Cy7Gal) based on a galactose derivative, to serve as substrate for β-galactosidase, conjugated to a Cy7 fluorophore modified with sulfonic groups to enhance its ability to diffuse. When administered to male or female mice, β-galactosidase cleaves the O-glycosidic bond, releasing the fluorophore that is ultimately excreted by the kidneys and can be measured in urine. The intensity of the recovered fluorophore reliably reflects an experimentally controlled load of cellular senescence and correlates with age-associated anxiety during aging and senolytic treatment. Interestingly, our findings with the probe indicate that the effects of senolysis are temporary if the treatment is discontinued. Our strategy may serve as a basis for developing fluorogenic platforms designed for easy longitudinal monitoring of enzymatic activities in biofluids.
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- 2024
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4. Water-Soluble Molecular Cages for Biological Applications
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Giovanni Montà-González, Eduardo Ortiz-Gómez, Rocío López-Lima, Guillermo Fiorini, Ramón Martínez-Máñez, and Vicente Martí-Centelles
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molecular cages ,host-guest chemistry ,anticancer applications ,supramolecular chemistry ,metal-organic cages ,organic cages ,Organic chemistry ,QD241-441 - Abstract
The field of molecular cages has attracted increasing interest in relation to the development of biological applications, as evidenced by the remarkable examples published in recent years. Two key factors have contributed to this achievement: First, the remarkable and adjustable host–guest chemical properties of molecular cages make them highly suitable for biological applications. This allows encapsulating therapeutic molecules to improve their properties. Second, significant advances have been made in synthetic methods to create water-soluble molecular cages. Achieving the necessary water solubility is a significant challenge, which in most cases requires specific chemical groups to overcome the inherent hydrophobic nature of the molecular cages which feature the organic components of the cage. This can be achieved by either incorporating water-solubilizing groups with negative/positive charges, polyethylene glycol chains, etc.; or by introducing charges directly into the cage structure itself. These synthetic strategies allow preparing water-soluble molecular cages for diverse biological applications, including cages’ anticancer activity, anticancer drug delivery, photodynamic therapy, and molecular recognition of biological molecules. In the review we describe selected examples that show the main concepts to achieve water solubility in molecular cages and some selected recent biological applications.
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- 2024
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5. Non-invasive biomarkers for mild cognitive impairment and Alzheimer's disease
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Marina Botello-Marabotto, M. Carmen Martínez-Bisbal, Miguel Calero, Andrea Bernardos, Ana B. Pastor, Miguel Medina, and Ramón Martínez-Máñez
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Metabolomics ,Alzheimer's disease ,Mild cognitive impairment ,NMR spectroscopy ,Biomarkers ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Alzheimer's disease is the most common type of dementia in the elderly. It is a progressive degenerative disorder that may begin to develop up to 15 years before clinical symptoms appear. The identification of early biomarkers is crucial to enable a prompt diagnosis and to start effective interventions. In this work, we conducted a metabolomic study using proton Nuclear Magnetic Resonance (1H NMR) spectroscopy in serum samples from patients with neuropathologically confirmed Alzheimer's disease (AD, n = 51), mild cognitive impairment (MCI, n = 27), and cognitively healthy controls (HC, n = 50) to search for metabolites that could be used as biomarkers. Patients and controls underwent yearly clinical follow-ups for up to six years. MCI group included samples from three subgroups of subjects with different disease progression rates. The first subgroup included subjects that remained clinically stable at the MCI stage during the period of study (stable MCI, S-MCI, n = 9). The second subgroup accounted for subjects which were diagnosed with MCI at the moment of blood extraction, but progressed to clinical dementia in subsequent years (MCI-to-dementia, MCI-D, n = 14). The last subgroup was composed of subjects that had been diagnosed as dementia for the first time at the moment of sample collection (incipient dementia, Incp-D, n = 4). Partial Least Square Discriminant Analysis (PLS-DA) models were developed. Three models were obtained, one to discriminate between AD and HC samples with high sensitivity (93.75%) and specificity (94.75%), another model to discriminate between AD and MCI samples (100% sensitivity and 82.35% specificity), and a last model to discriminate HC and MCI with lower sensitivity and specificity (67% and 50%). Differences within the MCI group were further studied in an attempt to determine those MCI subjects that could develop AD-type dementia in the future. The relative concentration of metabolites, and metabolic pathways were studied. Alterations in the pathways of alanine, aspartate and glutamate metabolism, pantothenate and CoA biosynthesis, and beta-alanine metabolism, were found when HC and MCI- D patients were compared. In contrast, no pathway was found disturbed in the comparison of S-MCI with HC groups. These results highlight the potential of 1H NMR metabolomics to support the diagnosis of dementia in a less invasive way, and set a starting point for the study of potential biomarkers to identify MCI or HC subjects at risk of developing AD in the future.
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- 2023
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6. Exploring the Synergy between Nano-Formulated Linezolid and Polymyxin B as a Gram-Negative Effective Antibiotic Delivery System Based on Mesoporous Silica Nanoparticles
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Ismael Otri, Serena Medaglia, Ramón Martínez-Máñez, Elena Aznar, and Félix Sancenón
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gated materials ,antimicrobials ,polymyxin B ,linezolid ,Chemistry ,QD1-999 - Abstract
Antimicrobial resistance is a current silent pandemic that needs new types of antimicrobial agents different from the classic antibiotics that are known to lose efficiency over time. Encapsulation of antibiotics inside nano-delivery systems could be a promising, effective strategy that is able to delay the capability of pathogens to develop resistance mechanisms against antimicrobials. These systems can be adapted to deliver already discovered antibiotics to specific infection sites in a more successful way. Herein, mesoporous silica nanomaterials are used for an efficient delivery of a linezolid gram-positive antibiotic that acts synergistically with gram-negative antimicrobial polymyxin B. For this purpose, linezolid is encapsulated in the pores of the mesoporous silica, whose outer surface is coated with a polymyxin B membrane disruptor. The nanomaterial showed a good controlled-release performance in the presence of lipopolysaccharide, found in bacteria cell membranes, and the complete bacteria E. coli DH5α. The performed studies demonstrate that when the novel formulation is near bacteria, polymyxin B interacts with the cell membrane, thereby promoting its permeation. After this step, linezolid can easily penetrate the bacteria and act with efficacy to kill the microorganism. The nano-delivery system presents a highly increased antimicrobial efficacy against gram-negative bacteria, where the use of free linezolid is not effective, with a fractional inhibitory concentration index of 0.0063 for E. coli. Moreover, enhanced toxicity against gram-positive bacteria was confirmed thanks to the combination of both antibiotics in the same nanoparticles. Although this new nanomaterial should be further studied to reach clinical practice, the obtained results pave the way to the development of new nanoformulations which could help in the fight against bacterial infections.
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- 2024
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7. miR‐99a‐5p modulates doxorubicin resistance via the COX‐2/ABCG2 axis in triple‐negative breast cancer: from the discovery to in vivo studies
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Iris Garrido‐Cano, Anna Adam‐Artigues, Ana Lameirinhas, Juan F. Blandez, Vicente Candela‐Noguera, Federico Rojo, Sandra Zazo, Juan Madoz‐Gúrpide, Ana Lluch, Begoña Bermejo, Felix Sancenón, Juan Miguel Cejalvo, Ramón Martínez‐Máñez, and Pilar Eroles
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Published
- 2022
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8. Toxicological Profiling and Long-Term Effects of Bare, PEGylated- and Galacto-Oligosaccharide-Functionalized Mesoporous Silica Nanoparticles
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Irene Barguilla, Vicente Candela-Noguera, Patrick Oliver, Balasubramanyam Annangi, Paula Díez, Elena Aznar, Ramón Martínez-Máñez, Ricard Marcos, Alba Hernández, and María Dolores Marcos
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mesoporous silica nanoparticles ,long-term effects ,toxicological profiling ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Mesoporous silica nanoparticles (MSNs) are amongst the most used nanoparticles in biomedicine. However, the potentially toxic effects of MSNs have not yet been fully evaluated, being a controversial matter in research. In this study, bare MSNs, PEGylated MSNs (MSNs-PEG), and galacto-oligosaccharide-functionalized MSNs (MSNs-GAL) are synthesized and characterized to assess their genotoxicity and transforming ability on human lung epithelial BEAS-2B cells in short- (48 h) and long-term (8 weeks) exposure scenarios. Initial short-term treatments show a dose-dependent increase in genotoxicity for MSNs-PEG-treated cells but not oxidative DNA damage for MSNs, MSNs-PEG, or for MSNs-GAL. In addition, after 8 weeks of continuous exposure, neither induced genotoxic nor oxidative DNA is observed. Nevertheless, long-term treatment with MSNs-PEG and MSNs-GAL, but not bare MSNs, induces cell transformation features, as evidenced by the cell’s enhanced ability to grow independently of anchorage, to migrate, and to invade. Further, the secretome from cells treated with MSNs and MSNs-GAL, but not MSNs-PEG, shows certain tumor-promoting abilities, increasing the number and size of HeLa cell colonies formed in the indirect soft-agar assay. These results show that MSNs, specifically the functionalized ones, provoke some measurable adverse effects linked to tumorigenesis. These effects are in the order of other nanomaterials, such as carbon nanotubes or cerium dioxide nanoparticles, but they are lower than those provoked by some approved drugs, such as doxorubicin or dexamethasone.
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- 2023
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9. Development of Photonic Multi-Sensing Systems Based on Molecular Gates Biorecognition and Plasmonic Sensors: The PHOTONGATE Project
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Oscar Nieves, David Ortiz de Zárate, Elena Aznar, Isabel Caballos, Eva Garrido, Ramón Martínez-Máñez, Fabian Dortu, Damien Bernier, Beatriz Mengual-Chuliá, F. Xavier López-Labrador, Jens J. Sloth, Katrin Loeschner, Lene Duedahl-Olesen, Natalia Prado, Martín Hervello, Armando Menéndez, Rainer Gransee, Thomas Klotzbuecher, M. Clara Gonçalves, Fahimeh Zare, Ana Fuentes López, Isabel Fernández Segovia, Jose M. Barat Baviera, Jaime Salcedo, Sara Recuero, Santiago Simón, Ana Fernández Blanco, Sergio Peransi, Maribel Gómez-Gómez, and Amadeu Griol
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photonics ,molecular gates ,localized surface plasmonic resonance (LSPR) ,porous silica ,biosensing ,microfluidics ,Chemical technology ,TP1-1185 - Abstract
This paper presents the concept of a novel adaptable sensing solution currently being developed under the EU Commission-founded PHOTONGATE project. This concept will allow for the quantification of multiple analytes of the same or different nature (chemicals, metals, bacteria, etc.) in a single test with levels of sensitivity and selectivity at/or over those offered by current solutions. PHOTONGATE relies on two core technologies: a biochemical technology (molecular gates), which will confer the specificity and, therefore, the capability to be adaptable to the analyte of interest, and which, combined with porous substrates, will increase the sensitivity, and a photonic technology based on localized surface plasmonic resonance (LSPR) structures that serve as transducers for light interaction. Both technologies are in the micron range, facilitating the integration of multiple sensors within a small area (mm2). The concept will be developed for its application in health diagnosis and food safety sectors. It is thought of as an easy-to-use modular concept, which will consist of the sensing module, mainly of a microfluidics cartridge that will house the photonic sensor, and a platform for fluidic handling, optical interrogation, and signal processing. The platform will include a new optical concept, which is fully European Union Made, avoiding optical fibers and expensive optical components.
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- 2023
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10. Pharmacological senolysis reduces doxorubicin-induced cardiotoxicity and improves cardiac function in mice
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Araceli Lérida-Viso, Alejandra Estepa- Fernández, Ángela Morellá-Aucejo, Beatriz Lozano-Torres, María Alfonso, Juan F. Blandez, Viviana Bisbal, Pilar Sepúlveda, Alba García-Fernández, Mar Orzáez, and Ramón Martínez-Máñez
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Doxorubicin ,Cardiac senescence ,Senolytic ,Navitoclax ,Nanoparticles ,Prodrug ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Many anticancer agents used in clinics induce premature senescence in healthy tissues generating accelerated aging processes and adverse side-effects in patients. Cardiotoxicity is a well-known limiting factor of anticancer treatment with doxorubicin (DOX), a very effective anthracycline widely used as antitumoral therapy in clinical practice, that leads to long-term morbidity and mortality. DOX exposure severely affects the population of cardiac cells in both mice and human hearts by inducing premature senescence, which may represent the molecular basis of DOX-induced cardiomyopathy. Here, we demonstrate that senescence induction in the heart contributes to impaired cardiac function in mice upon DOX treatment. Concomitant elimination of senescent cells with the senolytic Navitoclax in different formulations produces a significant decrease in senescence and cardiotoxicity markers together with the restoration of the cardiac function in mice followed by echocardiography. These results evidence the potential clinical use of senolytic therapies to alleviate cardiotoxicities induced in chemotherapy-treated patients.
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- 2022
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11. New bladder cancer non-invasive surveillance method based on voltammetric electronic tongue measurement of urine
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Javier Monreal-Trigo, Miguel Alcañiz, M. Carmen Martínez-Bisbal, Alba Loras, Lluís Pascual, José Luis Ruiz-Cerdá, Alberto Ferrer, and Ramón Martínez-Máñez
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Computer-aided diagnosis method ,Cancer ,Devices ,Science - Abstract
Summary: Bladder cancer (BC) is the sixth leading cause of death by cancer. Depending on the invasiveness of tumors, patients with BC will undergo surgery and surveillance lifelong, owing the high rate of recurrence and progression. In this context, the development of strategies to support non-invasive BC diagnosis is focusing attention. Voltammetric electronic tongue (VET) has been demonstrated to be of use in the analysis of biofluids. Here, we present the implementation of a VET to study 207 urines to discriminate BC and non-BC for diagnosis and surveillance to detect recurrences. Special attention has been paid to the experimental setup to improve reproducibility in the measurements. PLSDA analysis together with variable selection provided a model with high sensitivity, specificity, and area under the ROC curve AUC (0.844, 0.882, and 0.917, respectively). These results pave the way for the development of non-invasive low-cost and easy-to-use strategies to support BC diagnosis and follow-up.
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- 2022
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12. Mesoporous Silica Materials as an Emerging Tool for Cancer Immunotherapy
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Blanca Escriche‐Navarro, Andrea Escudero, Elena Lucena‐Sánchez, Félix Sancenón, Alba García‐Fernández, and Ramón Martínez‐Máñez
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cancer ,checkpoint inhibitors ,immunotherapy ,mesoporous silica nanoparticles ,photodynamic therapies ,vaccines ,Science - Abstract
Abstract Cancer immunotherapy has emerged in the past decade as a promising strategy for treating many forms of cancer by stimulating the patient's immune system. Although immunotherapy has achieved some promising results in clinics, more efforts are required to improve the limitations of current treatments related to lack of effective and targeted cancer antigens delivery to immune cells, dose‐limiting toxicity, and immune‐mediated adverse effects, among others. In recent years, the use of nanomaterials has proven promising to enhance cancer immunotherapy efficacy and reduce side effects. Among nanomaterials, attention has been recently paid to mesoporous silica nanoparticles (MSNs) as a potential multiplatform for enhancing cancer immunotherapy by considering their unique properties, such as high porosity, and good biocompatibility, facile surface modification, and self‐adjuvanticity. This review explores the role of MSN and other nano/micro‐materials as an emerging tool to enhance cancer immunotherapy, and it comprehensively summarizes the different immunotherapeutic strategies addressed to date by using MSN.
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- 2022
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13. Development of New Targeted Nanotherapy Combined with Magneto-Fluorescent Nanoparticles against Colorectal Cancer
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Gonçalo A. Marcelo, David Montpeyó, Joana Galhano, Ramón Martínez-Máñez, José Luis Capelo-Martínez, Julia Lorenzo, Carlos Lodeiro, and Elisabete Oliveira
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target nanocarriers ,oral formulations ,colorectal cancer ,target drug delivery ,targeted anticancer therapy ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The need for non-invasive therapies capable of conserving drug efficiency and stability while having specific targetability against colorectal cancer (CRC), has made nanoparticles preferable vehicles and principal building blocks for the development of complex and multi-action anti-tumoral approaches. For that purpose, we herein report the production of a combinatory anti-tumoral nanotherapy using the production of a new targeting towards CRC lines. To do so, Magneto-fluorescent NANO3 nanoparticles were used as nanocarriers for a combination of the drugs doxorubicin (DOX) and ofloxacin (OFLO). NANO3 nanoparticles’ surface was modified with two different targeting agents, a newly synthesized (anti-CA IX acetazolamide derivative (AZM-SH)) and a commercially available (anti-epidermal growth factor receptor (EGFR), Cetuximab). The cytotoxicity revealed that only DOX-containing nanosystems showed significant and even competitive cytotoxicity when compared to that of free DOX. Interestingly, surface modification with AZM-SH promoted an increased cellular uptake in the HCT116 cell line, surpassing even those functionalized with Cetuximab. The results show that the new target has high potential to be used as a nanotherapy agent for CRC cells, surpassing commercial targets. As a proof-of-concept, an oral administration form of NANO3 systems was successfully combined with Eudragit® enteric coating and studied under extreme conditions.
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- 2023
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14. Oligonucleotide-capped nanoporous anodic alumina biosensor as diagnostic tool for rapid and accurate detection of Candida auris in clinical samples
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Luis Pla, Sara Santiago-Felipe, María Ángeles Tormo-Mas, Alba Ruiz-Gaitán, Javier Pemán, Eulogio Valentín, Félix Sancenón, Elena Aznar, and Ramón Martínez-Máñez
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Nanoporous anodic alumina ,oligonucleotide ,molecular gates ,Candida auris ,biosensor ,rapid diagnosis ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
Candida auris has arisen as an important multidrug-resistant fungus because of several nosocomial outbreaks and elevated rates of mortality. Accurate and rapid diagnosis of C. auris is highly desired; nevertheless, current methods often present severe limitations and produce misidentification. Herein a sensitive, selective, and time-competitive biosensor based on oligonucleotide-gated nanomaterials for effective detection of C. auris is presented. In the proposed design, a nanoporous anodic alumina scaffold is filled with the fluorescent indicator rhodamine B and the pores blocked with different oligonucleotides capable of specifically recognize C. auris genomic DNA. Gate opening modulation and cargo delivery is controlled by successful DNA recognition. C. auris is detected at a concentration as low as 6 CFU/mL allowing obtaining a diagnostic result in clinical samples in one hour with no prior DNA extraction or amplification steps.
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- 2021
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15. In Situ-Forming Gels Loaded with Stimuli-Responsive Gated Mesoporous Silica Nanoparticles for Local Sustained Drug Delivery
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Cristina de la Torre, Carmen Coll, Amelia Ultimo, Félix Sancenón, Ramón Martínez-Máñez, and Eduardo Ruiz-Hernández
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mesoporous silica ,drug delivery ,molecular gates ,in situ-forming gels ,Pharmacy and materia medica ,RS1-441 - Abstract
A novel combination of in situ-forming hydrogels of hyaluronic acid with gated mesoporous materials was developed to design depots for local sustained release of chemotherapeutics. The depot consists of a hyaluronic-based gel loaded with redox-responsive mesoporous silica nanoparticles loaded with safranin O or doxorubicin and capped with polyethylene glycol chains containing a disulfide bond. The nanoparticles are able to deliver the payload in the presence of the reducing agent, glutathione (GSH), that promotes the cleavage of the disulfide bonds and the consequent pore opening and cargo delivery. Release studies and cellular assays demonstrated that the depot can successfully liberate the nanoparticles to the media and, subsequently, that the nanoparticles are internalized into the cells where the high concentration of GSH induces cargo delivery. When the nanoparticles were loaded with doxorubicin, a significant reduction in cell viability was observed. Our research opens the way to the development of new depots that enhance the local controlled release of chemotherapeutics by combining the tunable properties of hyaluronic gels with a wide range of gated materials.
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- 2023
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16. Finite Element Models of Gold Nanoparticles and Their Suspensions for Photothermal Effect Calculation
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José Manuel Terrés-Haro, Javier Monreal-Trigo, Andy Hernández-Montoto, Francisco Javier Ibáñez-Civera, Rafael Masot-Peris, and Ramón Martínez-Máñez
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Finite Element Methods ,metal nanoparticles ,plasmonics ,photothermal effect ,Technology ,Biology (General) ,QH301-705.5 - Abstract
(1) Background: The ability of metal nanoparticles to carry other molecules and their electromagnetic interactions can be used for localized drug release or to heat malignant tissue, as in the case of photothermal treatments. Plasmonics can be used to calculate their absorption and electric field enhancement, which can be further used to predict the outcome of photothermal experiments. In this study, we model the nanoparticle geometry in a Finite Element Model calculus environment to calculate the effects that occur as a response to placing it in an optical, electromagnetic field, and also a model of the experimental procedure to measure the temperature rise while irradiating a suspension of nanoparticles. (2) Methods: Finite Element Method numerical models using the COMSOL interface for geometry and mesh generation and iterative solving discretized Maxwell’s equations; (3) Results: Absorption and scattering cross-section spectrums were obtained for NanoRods and NanoStars, also varying their geometry as a parameter, along with electric field enhancement in their surroundings; temperature curves were calculated and measured as an outcome of the irradiation of different concentration suspensions; (4) Conclusions: The results obtained are comparable with the bibliography and experimental measurements.
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- 2023
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17. High-Capacity Mesoporous Silica Nanocarriers of siRNA for Applications in Retinal Delivery
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Amelia Ultimo, Mar Orzaez, Maria J. Santos-Martinez, Ramón Martínez-Máñez, María D. Marcos, Félix Sancenón, and Eduardo Ruiz-Hernández
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age-related macular degeneration ,large pore mesoporous silica nanoparticles ,siRNA delivery ,VEGF silencing ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The main cause of subretinal neovascularisation in wet age-related macular degeneration (AMD) is an abnormal expression in the retinal pigment epithelium (RPE) of the vascular endothelial growth factor (VEGF). Current approaches for the treatment of AMD present considerable issues that could be overcome by encapsulating anti-VEGF drugs in suitable nanocarriers, thus providing better penetration, higher retention times, and sustained release. In this work, the ability of large pore mesoporous silica nanoparticles (LP-MSNs) to transport and protect nucleic acid molecules is exploited to develop an innovative LP-MSN-based nanosystem for the topical administration of anti-VEGF siRNA molecules to RPE cells. siRNA is loaded into LP-MSN mesopores, while the external surface of the nanodevices is functionalised with polyethylenimine (PEI) chains that allow the controlled release of siRNA and promote endosomal escape to facilitate cytosolic delivery of the cargo. The successful results obtained for VEGF silencing in ARPE-19 RPE cells demonstrate that the designed nanodevice is suitable as an siRNA transporter.
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- 2023
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18. Not always what closes best opens better: mesoporous nanoparticles capped with organic gates
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Elena Añón, Ana M. Costero, Pablo Gaviña, Margarita Parra, Jamal El Haskouri, Pedro Amorós, Ramón Martínez-Máñez, and Félix Sancenón
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mesoporous nanoparticles ,gated nanodevices ,esterase controlled release ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Biotechnology ,TP248.13-248.65 - Abstract
Four types of calcined MCM-41 silica nanoparticles, loaded with dyes and capped with different gating ensembles are prepared and characterized. N1 and N2 nanoparticles are loaded with rhodamine 6G and capped with bulky poly(ethylene glycol) derivatives bearing ester groups (1 and 2). N3-N4 nanoparticles are loaded with sulforhodamine B and capped with self-immolative derivatives bearing ester moieties. In the absence of esterase enzyme negligible cargo release from N1, N3 and N4 nanoparticles is observed whereas a remarkable release for N2 is obtained most likely due to the formation of an irregular coating on the outer surface of the nanoparticles. In contrast, a marked delivery is found in N1, N3, and N4 in the presence of esterase enzyme. The delivery rate is related to the hydrophilic/hydrophobic character of the coating shell. The use of hydrophilic poly(ethylene glycol) derivatives as gating ensembles on N1 and N2 enables an easy access of esterase to the ester moieties with subsequent fast cargo release. On the other hand, the presence of a hydrophobic monolayer on N3 and N4 partially hinders esterase enzyme access to the ester groups and the rate of cargo release was decreased.
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- 2019
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19. Magneto-Fluorescent Mesoporous Nanocarriers for the Dual-Delivery of Ofloxacin and Doxorubicin to Tackle Opportunistic Bacterial Infections in Colorectal Cancer
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Gonçalo A. Marcelo, Joana Galhano, Tiago T. Robalo, Maria Margarida Cruz, María D. Marcos, Ramón Martínez-Máñez, Maria Paula Duarte, José Luis Capelo-Martínez, Carlos Lodeiro, and Elisabete Oliveira
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magneto-fluorescence ,mesoporous nanoparticles ,drug delivery ,hyperthermia ,antimicrobial ,opportunistic cancer-related bacteria ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Cancer-related opportunistic bacterial infections are one major barrier for successful clinical therapies, often correlated to the production of genotoxic factors and higher cancer incidence. Although dual anticancer and antimicrobial therapies are a growing therapeutic fashion, they still fall short when it comes to specific delivery and local action in in vivo systems. Nanoparticles are seen as potential therapeutic vectors, be it by means of their intrinsic antibacterial properties and effective delivery capacity, or by means of their repeatedly reported modulation and maneuverability. Herein we report on the production of a biocompatible, antimicrobial magneto-fluorescent nanosystem (NANO3) for the delivery of a dual doxorubicin–ofloxacin formulation against cancer-related bacterial infections. The drug delivery capacity, rendered by its mesoporous silica matrix, is confirmed by the high loading capacity and stimuli-driven release of both drugs, with preference for tumor-like acidic media. The pH-dependent emission of its surface fluorescent SiQDs, provides an insight into NANO3 surface behavior and pore availability, with the SiQDs working as pore gates. Hyperthermia induces heat generation to febrile temperatures, doubling drug release. NANO3-loaded systems demonstrate significant antimicrobial activity, specifically after the application of hyperthermia conditions. NANO3 structure and antimicrobial properties confirm their potential use in a future dual anticancer and antimicrobial therapeutical vector, due to their drug loading capacity and their surface availability for further modification with bioactive, targeting species.
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- 2022
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20. Gated Organonanoclays for Large Biomolecules: Controlled Release Triggered by Surfactant Stimulus
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Elisa Poyatos-Racionero, Édgar Pérez-Esteve, Serena Medaglia, Elena Aznar, José M. Barat, Ramón Martínez-Máñez, Maria Dolores Marcos, and Andrea Bernardos
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organonanoclay ,hematin ,cyanocobalamin ,oleic acid ,surfactant ,controlled release ,Chemistry ,QD1-999 - Abstract
The low toxicity and high adsorption capacities of clay minerals make them attractive for controlled delivery applications. However, the number of controlled-release studies in the literature using clay minerals is still scarce. In this work, three different clays from the smectite group (Kunipia F, montmorillonite; Sumecton SA, saponite; and Sumecton SWN, hectorite) were successfully loaded with rhodamine B dye and functionalized with oleic acid as a gatekeeper to produce organonanoclays for active and controlled payload-release. Moreover, hematin and cyanocobalamin have also been encapsulated in hectorite gated clay. These organonanoclays were able to confine the entrapped cargos in an aqueous environment, and effectively release them in the presence of surfactants (as bile salts). A controlled delivery of 49 ± 6 μg hematin/mg solid and 32.7 ± 1.5 μg cyanocobalamin/mg solid was reached. The cargo release profiles of all of the organonanoclays were adjusted to three different release-kinetic models, demonstrating the Korsmeyer–Peppas model with release dependence on (i) the organic–inorganic hybrid system, and (ii) the nature of loaded molecules and their interaction with the support. Furthermore, in vitro cell viability assays were carried out with Caco-2 cells, demonstrating that the organonanoclays are well tolerated by cells at particle concentrations of ca. 50 μg/mL.
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- 2022
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21. Nanodevices for the Efficient Codelivery of CRISPR-Cas9 Editing Machinery and an Entrapped Cargo: A Proposal for Dual Anti-Inflammatory Therapy
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Alba García-Fernández, Gema Vivo-Llorca, Mónica Sancho, Alicia Belén García-Jareño, Laura Ramírez-Jiménez, Eloísa Barber-Cano, José Ramón Murguía, Mar Orzáez, Félix Sancenón, and Ramón Martínez-Máñez
- Subjects
mesoporous silica nanoparticles ,CRISPR-Cas9 ,gene editing ,inflammation ,drug delivery ,Pharmacy and materia medica ,RS1-441 - Abstract
In this article, we report one of the few examples of nanoparticles capable of simultaneously delivering CRISPR-Cas9 gene-editing machinery and releasing drugs for one-shot treatments. Considering the complexity of inflammation in diseases, the synergistic effect of nanoparticles for gene-editing/drug therapy is evaluated in an in vitro inflammatory model as proof of concept. Mesoporous silica nanoparticles (MSNs), able to deliver the CRISPR/Cas9 machinery to edit gasdermin D (GSDMD), a key protein involved in inflammatory cell death, and the anti-inflammatory drug VX-765 (GSDMD45CRISPR-VX-MSNs), were prepared. Nanoparticles allow high cargo loading and CRISPR-Cas9 plasmid protection and, thus, achieve the controlled codelivery of CRISPR-Cas9 and the drug in cells. Nanoparticles exhibit GSDMD gene editing by downregulating inflammatory cell death and achieving a combined effect on decreasing the inflammatory response by the codelivery of VX-765. Taken together, our results show the potential of MSNs as a versatile platform by allowing multiple combinations for gene editing and drug therapy to prepare advanced nanodevices to meet possible biomedical needs.
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- 2022
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22. Vascular Senescence: A Potential Bridge Between Physiological Aging and Neurogenic Decline
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Sara Rojas-Vázquez, Laura Blasco-Chamarro, Irene López-Fabuel, Ramón Martínez-Máñez, and Isabel Fariñas
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adult neural stem cell ,neurogenic niche ,endothelial cell senescence ,senescence-associated secretory phenotype ,parabiosis ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
The adult mammalian brain contains distinct neurogenic niches harboring populations of neural stem cells (NSCs) with the capacity to sustain the generation of specific subtypes of neurons during the lifetime. However, their ability to produce new progeny declines with age. The microenvironment of these specialized niches provides multiple cellular and molecular signals that condition NSC behavior and potential. Among the different niche components, vasculature has gained increasing interest over the years due to its undeniable role in NSC regulation and its therapeutic potential for neurogenesis enhancement. NSCs are uniquely positioned to receive both locally secreted factors and adhesion-mediated signals derived from vascular elements. Furthermore, studies of parabiosis indicate that NSCs are also exposed to blood-borne factors, sensing and responding to the systemic circulation. Both structural and functional alterations occur in vasculature with age at the cellular level that can affect the proper extrinsic regulation of NSCs. Additionally, blood exchange experiments in heterochronic parabionts have revealed that age-associated changes in blood composition also contribute to adult neurogenesis impairment in the elderly. Although the mechanisms of vascular- or blood-derived signaling in aging are still not fully understood, a general feature of organismal aging is the accumulation of senescent cells, which act as sources of inflammatory and other detrimental signals that can negatively impact on neighboring cells. This review focuses on the interactions between vascular senescence, circulating pro-senescence factors and the decrease in NSC potential during aging. Understanding the mechanisms of NSC dynamics in the aging brain could lead to new therapeutic approaches, potentially include senolysis, to target age-dependent brain decline.
- Published
- 2021
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23. Fluorogenic Detection of Human Serum Albumin Using Curcumin-Capped Mesoporous Silica Nanoparticles
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Ismael Otri, Serena Medaglia, Elena Aznar, Félix Sancenón, and Ramón Martínez-Máñez
- Subjects
mesoporous silica ,gated hybrid materials ,sensors ,HSA detection ,Organic chemistry ,QD241-441 - Abstract
Mesoporous silica nanoparticles loaded with rhodamine B and capped with curcumin are used for the selective and sensitive fluorogenic detection of human serum albumin (HSA). The sensing mesoporous silica nanoparticles are loaded with rhodamine B, decorated with aminopropyl moieties and capped with curcumin. The nanoparticles selectively release the rhodamine B cargo in the presence of HSA. A limit of detection for HSA of 0.1 mg/mL in PBS (pH 7.4)-acetonitrile 95:5 v/v was found, and the sensing nanoparticles were used to detect HSA in spiked synthetic urine samples.
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- 2022
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24. Avidin-gated mesoporous silica nanoparticles for signal amplification in electrochemical biosensor
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Sandra Jimenez-Falcao, Jorge Parra-Nieto, Hugo Pérez-Cuadrado, Ramón Martínez-Máñez, Paloma Martínez-Ruiz, and Reynaldo Villalonga
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Industrial electrochemistry ,TP250-261 ,Chemistry ,QD1-999 - Abstract
We report herein a novel sensing strategy for electrochemical biosensors, by using mesoporous silica nanoparticles loaded with the redox probe methylene blue and capped with an avidin/imminobiotin stimulus-responsive gate-like ensemble as signal amplification element. As a proof of concept, an aptasensor for carcinoembryonic antigen (CEA) was constructed by attaching a biotin and thiol-functionalized anti-CEA DNA hairpin aptamer on gold nanoparticles modified carbon screen-printed electrodes. The biosensing approach relied on the unfolding of the aptamer molecule after specific recognition of CEA, unmasking the biotin residue and allowing further association with the avidin-capped mesoporous nanocarrier. Incubation with H2SO4 trigger the release of the encapsulated redox probe allowing the detection of the cancer biomarker from 1.0 pg/mL to 160 ng/mL. Keywords: Aptamer, Biosensor, Carcinoembryonic antigen, Mesoporous silica nanoparticles, Signal amplification
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- 2019
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25. Sucrose-Responsive Intercommunicated Janus Nanoparticles Network
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Sandra Jimenez-Falcao, Daniel Torres, Paloma Martínez-Ruiz, Diana Vilela, Ramón Martínez-Máñez, and Reynaldo Villalonga
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network ,Janus particles ,enzymatic control ,nanodevices ,intercommunication ,Chemistry ,QD1-999 - Abstract
Inspired by biological systems, the development of artificial nanoscale materials that communicate over a short distance is still at its early stages. This work shows a new example of a cooperating system with intercommunicated devices at the nanoscale. The system is based on the new sucrose-responsive Janus gold-mesoporous silica (Janus Au-MS) nanoparticles network with two enzyme-powered nanodevices. These nanodevices involve two enzymatic processes based on invertase and glucose oxidase, which are anchored on the Au surfaces of different Janus Au-MS nanoparticles, and N-acetyl-L-cysteine and [Ru(bpy)3]2+ loaded as chemical messengers, respectively. Sucrose acts as the INPUT, triggering the sequential delivery of two different cargoes through the enzymatic control. Nanoscale communication using abiotic nanodevices is a developing potential research field and may prompt several applications in different disciplines, such as nanomedicine.
- Published
- 2021
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26. The Effectiveness of Glutathione Redox Status as a Possible Tumor Marker in Colorectal Cancer
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Delia Acevedo-León, Lidia Monzó-Beltrán, Segundo Ángel Gómez-Abril, Nuria Estañ-Capell, Natalia Camarasa-Lillo, Marisa Luisa Pérez-Ebri, Jorge Escandón-Álvarez, Eulalia Alonso-Iglesias, Marisa Luisa Santaolaria-Ayora, Araceli Carbonell-Moncho, Josep Ventura-Gayete, Luis Pla, Maria Carmen Martínez-Bisbal, Ramón Martínez-Máñez, Leticia Bagán-Debón, Aurora Viña-Almunia, M. Amparo Martínez-Santamaría, María Ruiz-Luque, Jorge Alonso-Fernández, Celia Bañuls, and Guillermo Sáez
- Subjects
colorectal cancer ,oxidative stress ,GSH ,GSSG ,GSSG/GSH redox state ,tumor markers ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The role of oxidative stress (OS) in cancer is a matter of great interest due to the implication of reactive oxygen species (ROS) and their oxidation products in the initiation of tumorigenesis, its progression, and metastatic dissemination. Great efforts have been made to identify the mechanisms of ROS-induced carcinogenesis; however, the validation of OS byproducts as potential tumor markers (TMs) remains to be established. This interventional study included a total of 80 colorectal cancer (CRC) patients and 60 controls. By measuring reduced glutathione (GSH), its oxidized form (GSSG), and the glutathione redox state in terms of the GSSG/GSH ratio in the serum of CRC patients, we identified significant changes as compared to healthy subjects. These findings are compatible with the effectiveness of glutathione as a TM. The thiol redox state showed a significant increase towards oxidation in the CRC group and correlated significantly with both the tumor state and the clinical evolution. The sensitivity and specificity of serum glutathione levels are far above those of the classical TMs CEA and CA19.9. We conclude that the GSSG/GSH ratio is a simple assay which could be validated as a novel clinical TM for the diagnosis and monitoring of CRC.
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- 2021
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27. Lactose-Gated Mesoporous Silica Particles for Intestinal Controlled Delivery of Essential Oil Components: An In Vitro and In Vivo Study
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Elisa Poyatos-Racionero, Isabel González-Álvarez, Paola Sánchez-Moreno, Leopoldo Sitia, Francesca Gatto, Pier Paolo Pompa, Elena Aznar, Marta González-Álvarez, Ramón Martínez-Máñez, María Dolores Marcos, and Andrea Bernardos
- Subjects
essential oil components ,mesoporous silica microparticles ,controlled release ,small intestine ,in vitro and in vivo intestinal models ,lactase enzyme ,Pharmacy and materia medica ,RS1-441 - Abstract
Mesoporous silica microparticles functionalized with lactose for the specific release of essential oil components (EOCs) in the small intestine are presented. In vitro and in vivo intestinal models were applied to validate the microparticles (M41-EOC-L), in which the presence of lactase acts as the triggering stimulus for the controlled release of EOCs. Among the different microdevices prepared (containing thymol, eugenol and cinnamaldehyde), the one loaded with cinnamaldehyde showed the most significant Caco-2 cell viability reduction. On the other hand, interaction of the particles with enterocyte-like monolayers showed a reduction of EOCs permeability when protected into the designed microdevices. Then, a microdevice loaded with cinnamaldehyde was applied in the in vivo model of Wistar rat. The results showed a reduction in cinnamaldehyde plasma levels and an increase in its concentration in the lumen of the gastrointestinal tract (GIT). The absence of payload release in the stomach, the progressive release throughout the intestine and the prolonged stay of the payload in the GIT-lumen increased the bioavailability of the encapsulated compound at the site of the desired action. These innovative results, based on the specific intestinal controlled delivery, suggest that the M41-payload-L could be a potential hybrid microdevice for the protection and administration of bioactive molecules in the small intestine and colon.
- Published
- 2021
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28. Secreted Enzyme-Responsive System for Controlled Antifungal Agent Release
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Andrea Bernardos, Matěj Božik, Ana Montero, Édgar Pérez-Esteve, Esther García-Casado, Miloslav Lhotka, Adéla Fraňková, María Dolores Marcos, José Manuel Barat, Ramón Martínez-Máñez, and Pavel Klouček
- Subjects
nanoparticles ,essential oil component ,antimicrobial ,antifungal ,exogenous enzyme ,Aspergillus niger ,Chemistry ,QD1-999 - Abstract
Essential oil components (EOCs) such as eugenol play a significant role in plant antimicrobial defense. Due to the volatility and general reactivity of these molecules, plants have evolved smart systems for their storage and release, which are key prerequisites for their efficient use. In this study, biomimetic systems for the controlled release of eugenol, inspired by natural plant defense mechanisms, were prepared and their antifungal activity is described. Delivery and antifungal studies of mesoporous silica nanoparticles (MSN) loaded with eugenol and capped with different saccharide gates—starch, maltodextrin, maltose and glucose—against fungus Aspergillus niger—were performed. The maltodextrin- and maltose-capped systems show very low eugenol release in the absence of the fungus Aspergillus niger but high cargo delivery in its presence. The anchored saccharides are degraded by exogenous enzymes, resulting in eugenol release and efficient inhibition of fungal growth.
- Published
- 2021
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29. Gene-Directed Enzyme Prodrug Therapy by Dendrimer-Like Mesoporous Silica Nanoparticles against Tumor Cells
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Vicente Candela-Noguera, Gema Vivo-Llorca, Borja Díaz de Greñu, María Alfonso, Elena Aznar, Mar Orzáez, María Dolores Marcos, Félix Sancenón, and Ramón Martínez-Máñez
- Subjects
GDEPT ,DMSNs ,tumor treatment ,drug delivery ,Chemistry ,QD1-999 - Abstract
We report herein a gene-directed enzyme prodrug therapy (GDEPT) system using gated mesoporous silica nanoparticles (MSNs) in an attempt to combine the reduction of side effects characteristic of GDEPT with improved pharmacokinetics promoted by gated MSNs. The system consists of the transfection of cancer cells with a plasmid controlled by the cytomegalovirus promoter, which promotes β-galactosidase (β-gal) expression from the bacterial gene lacZ (CMV-lacZ). Moreover, dendrimer-like mesoporous silica nanoparticles (DMSNs) are loaded with the prodrug doxorubicin modified with a galactose unit through a self-immolative group (DOXO-Gal) and modified with a disulfide-containing polyethyleneglycol gatekeeper. Once in tumor cells, the reducing environment induces disulfide bond rupture in the gatekeeper with the subsequent DOXO-Gal delivery, which is enzymatically converted by β-gal into the cytotoxic doxorubicin drug, causing cell death. The combined treatment of the pair enzyme/DMSNs-prodrug are more effective in killing cells than the free prodrug DOXO-Gal alone in cells transfected with β-gal.
- Published
- 2021
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30. Towards the Enhancement of Essential Oil Components’ Antimicrobial Activity Using New Zein Protein-Gated Mesoporous Silica Microdevices
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Elisa Poyatos-Racionero, Gemma Guarí-Borràs, María Ruiz-Rico, Ángela Morellá-Aucejo, Elena Aznar, José Manuel Barat, Ramón Martínez-Máñez, María Dolores Marcos, and Andrea Bernardos
- Subjects
mesoporous silica particles ,zein ,corn ,molecular gate ,protease secretion ,E. coli ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The development of new food preservatives is essential to prevent foodborne outbreaks or food spoilage due to microbial growth, enzymatic activity or oxidation. Furthermore, new compounds that substitute the commonly used synthetic food preservatives are needed to stifle the rising problem of microbial resistance. In this scenario, we report herein, as far as we know, for the first time the use of the zein protein as a gating moiety and its application for the controlled release of essential oil components (EOCs). The design of microdevices consist of mesoporous silica particles loaded with essential oils components (thymol, carvacrol and cinnamaldehyde) and functionalized with the zein (prolamin) protein found in corn as a molecular gate. The zein protein grafted on the synthesized microdevices is degraded by the proteolytic action of bacterial enzymatic secretions with the consequent release of the loaded essential oil components efficiently inhibiting bacterial growth. The results allow us to conclude that the new microdevice presented here loaded with the essential oil component cinnamaldehyde improved the antimicrobial properties of the free compound by decreasing volatility and increasing local concentration.
- Published
- 2021
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31. Interactive models of communication at the nanoscale using nanoparticles that talk to one another
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Antoni Llopis-Lorente, Paula Díez, Alfredo Sánchez, María D. Marcos, Félix Sancenón, Paloma Martínez-Ruiz, Reynaldo Villalonga, and Ramón Martínez-Máñez
- Subjects
Science - Abstract
In the interactive model of communication, information is exchanged bidirectionally between a sender and receiver. Here, the authors realise interactive communication between two artificial nanoparticles, which relay information between each other in the form of chemical messengers and enzymatic reactions.
- Published
- 2017
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32. pH-Dependent Molecular Gate Mesoporous Microparticles for Biological Control of Giardia intestinalis
- Author
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Isabel González-Alvarez, Verónica Vivancos, Carmen Coll, Bárbara Sánchez-Dengra, Elena Aznar, Alejandro Ruiz-Picazo, Marival Bermejo, Félix Sancenón, María Auxiliadora Dea-Ayuela, Marta Gonzalez-Alvarez, and Ramón Martínez-Máñez
- Subjects
mesoporous microparticles ,G. intestinalis ,molecular gate ,targeted drug delivery ,oral administration ,Pharmacy and materia medica ,RS1-441 - Abstract
Giardiasis is a parasitism produced by the protozoa Giardia intestinalis that lives as trophozoite in the small intestine (mainly in the duodenum) attached to the intestinal villus by means of billed discs. The first line treatment is metronidazole, a drug with high bioavailability, which is why to obtain therapeutic concentrations in duodenum, it is necessary to administer high doses of drug to patients with the consequent occurrence of side effects. It is necessary to developed new therapeutical approaches to achieve a local delivery of the drug. In this sense, we have developed gated mesoporous silica microparticles loaded with metronidazole and with a molecular gate pH dependent. In vitro assays demonstrated that the metronidazole release is practically insignificant at acidic pHs, but in duodenum conditions, the metronidazole delivery from the microparticles is effective enough to produce an important parasite destruction. In vivo assays indicate that this microparticulate system allows to increase the concentration of the drug in duodenum and reduce the concentration in plasma avoiding systemic effects. This system could be useful for other intestinal local treatments in order to reduce doses and increase drug availability in target tissues.
- Published
- 2021
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33. Triplex Hybridization-Based Nanosystem for the Rapid Screening of Pneumocystis Pneumonia in Clinical Samples
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Luis Pla, Anna Aviñó, Ramón Eritja, Alba Ruiz-Gaitán, Javier Pemán, Vicente Friaza, Enrique J. Calderón, Elena Aznar, Ramón Martínez-Máñez, and Sara Santiago-Felipe
- Subjects
nanoporous anodic alumina ,Pneumocystis jirovecii ,molecular gates ,oligonucleotides ,biosensor ,Biology (General) ,QH301-705.5 - Abstract
Pneumocystis pneumonia (PcP) is a disease produced by the opportunistic infection of the fungus Pneumocystis jirovecii. As delayed or unsuitable treatments increase the risk of mortality, the development of rapid and accurate diagnostic tools for PcP are of great importance. Unfortunately, current standard methods present severe limitations and are far from adequate. In this work, a time-competitive, sensitive and selective biosensor based on DNA-gated nanomaterials for the identification of P. jirovecii is presented. The biosensor consists of a nanoporous anodic alumina (NAA) scaffold which pores are filled with a dye reporter and capped with specific DNA oligonucleotides. In the presence of P. jirovecii genomic DNA, the gated biosensor is open, and the cargo is delivered to the solution where it is monitored through fluorescence spectroscopy. The use of capping oligonucleotides able to form duplex or triplex with P. jirovecii DNA is studied. The final diagnostic tool shows a limit of detection (LOD) of 1 nM of target complementary DNA and does not require previous amplification steps. The method was applied to identify DNA from P. jirovecii in unmodified bronchoalveolar lavage, nasopharyngeal aspirates, and sputum samples in 60 min. This is a promising alternative method for the routinely diagnosis of Pneumocystis pneumonia.
- Published
- 2020
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34. Antibacterial Activity of Linezolid against Gram-Negative Bacteria: Utilization of ε-Poly-l-Lysine Capped Silica Xerogel as an Activating Carrier
- Author
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Gulcihan Guzel Kaya, Serena Medaglia, Vicente Candela-Noguera, María Ángeles Tormo-Mas, María Dolores Marcos, Elena Aznar, Huseyin Deveci, and Ramón Martínez-Máñez
- Subjects
antibacterial activity ,linezolid ,mesoporous material ,silica xerogel ,ε-poly-l-lysine ,Pharmacy and materia medica ,RS1-441 - Abstract
In recent times, many approaches have been developed against drug resistant Gram-negative bacteria. However, low-cost high effective materials which could broaden the spectrum of antibiotics are still needed. In this study, enhancement of linezolid spectrum, normally active against Gram-positive bacteria, was aimed for Gram-negative bacteria growth inhibition. For this purpose, a silica xerogel prepared from a low-cost precursor is used as a drug carrier owing to the advantages of its mesoporous structure, suitable pore and particle size and ultralow density. The silica xerogel is loaded with linezolid and capped with ε-poly-l-lysine. The developed nano-formulation shows a marked antibacterial activity against to Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. In comparison to free linezolid and ε-poly-l-lysine, the material demonstrates a synergistic effect on killing for the three tested bacteria. The results show that silica xerogels can be used as a potential drug carrier and activity enhancer. This strategy could provide the improvement of antibacterial activity spectrum of antibacterial agents like linezolid and could represent a powerful alternative to overcome antibiotic resistance in a near future.
- Published
- 2020
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35. Surfactant-Triggered Molecular Gate Tested on Different Mesoporous Silica Supports for Gastrointestinal Controlled Delivery
- Author
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Elisa Poyatos-Racionero, Isabel González-Álvarez, Marta González-Álvarez, Ramón Martínez-Máñez, M. Dolores Marcos, Andrea Bernardos, and Elena Aznar
- Subjects
mesoporous silica ,oleic acid ,molecular gate ,MCM-41 ,MCM-48 ,SBA-15 ,Chemistry ,QD1-999 - Abstract
In recent decades, the versatility of mesoporous silica particles and their relevance to develop controlled release systems have been demonstrated. Within them, gated materials able to modulate payload delivery represent great advantages. However, the role played by the porous matrix in this kind of systems is scarce. In this work, different mesoporous silica materials (MCM-41, MCM-48, SBA-15 and UVM-7) are functionalized with oleic acid as a molecular gate. All systems are fully characterized and their ability to confine the entrapped cargo and release it in the presence of bile salts is validated with release assays and in vitro digestion experiments. The cargo release profile of each synthesized support is studied, paying attention to the inorganic scaffold. Obtained release profiles fit to Korsmeyer–Peppas model, which explains the differences among the studied supports. Based on the results, UVM-7 material was the most appropriate system for duodenal delivery and was tested in an in vivo model of the Wistar rat. Payload confinement and its complete release after gastric emptying is achieved, establishing the possible use of mesoporous silica particles as protection and direct release agents into the duodenum and, hence, demonstrating that these systems could serve as an alternative to the administration methods employed until now.
- Published
- 2020
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36. Gold Nanoparticle-Assisted Virus Formation by Means of the Delivery of an Oncolytic Adenovirus Genome
- Author
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Luis Sendra, Antonio Miguel, M. Carmen Navarro-Plaza, María José Herrero, José de la Higuera, Consuelo Cháfer-Pericás, Elena Aznar, M. Dolores Marcos, Ramón Martínez-Máñez, Luis Alfonso Rojas, Ramón Alemany, and Salvador F. Aliño
- Subjects
gold nanoparticles ,delivery ,gene therapy ,non-viral vectors ,oncolytic virus ,virotherapy ,Chemistry ,QD1-999 - Abstract
Oncolytic adenoviruses are a therapeutic alternative to treat cancer based on their ability to replicate selectively in tumor cells. However, their use is limited mainly by the neutralizing antibody (Nab) immune response that prevents repeated dosing. An alternative to facilitate the DNA access to the tumor even in the presence of anti-viral Nabs could be gold nanoparticles able to transfer DNA molecules. However, the ability of these nanoparticles to carry large DNA molecules, such as an oncolytic adenovirus genome, has not been studied. In this work, gold nanoparticles were functionalized with different amounts of polyethylenimine to transfer in a safe and efficient manner a large oncolytic virus genome. Their transfer efficacy and final effect of the oncolytic virus in cancer cells are studied. For each synthesized nanoparticle, (a) DNA loading capacity, (b) complex size, (c) DNA protection ability, (d) transfection efficacy and (e) cytotoxic effect were studied. We observed that small gold nanoparticles (70–80 nm in diameter) protected DNA against nucleases and were able to transfect the ICOVIR-15 oncolytic virus genome encoded in pLR1 plasmid. In the present work, efficient transgene RNA expression, luciferase activity and viral cytopathic effect on cancer cells are reported. These results suggest gold nanoparticles to be an efficient and safe vector for oncolytic adenovirus genome transfer.
- Published
- 2020
- Full Text
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37. Study of Fishmeal Substitution on Growth Performance and Shelf-Life of Giltheadsea Bream (Sparusaurata)
- Author
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Patricia Zaragozá, Silvia Martínez-Llorens, Isabel Fernández-Segovia, José-Luis Vivancos, Ana Tomas-Vidal, Ana Fuentes, José Vicente Ros-Lis, Ramón Martínez-Máñez, and José Manuel Barat
- Subjects
Sparusaurata ,giltheadsea bream ,fishmeal ,plantprotein ,shelf-life ,colorimetric sensor array ,Biology (General) ,QH301-705.5 ,Genetics ,QH426-470 - Abstract
In this work the effect of partial or total replacement of fishmeal by plant protein sources and krill and squid meal on growth performance and shelf-life of gilthead sea bream was evaluated. Plant protein dietswith 50 g kg−1 of krill and 100 g kg−1 of squid were supplemented with synthetic amino acidsand at the end of the growing period weight showed no significant differences. The spoilage process of the fish was followed by physicochemical and microbiological measurements together with a colorimetric sensor array (CSA) specially designed for that purpose. The changes in the physicochemical parameters and microbial growth showed that shelf-life of samples were in all cases lower than ninedays. The CSA was not able to show significant differences between both diets, confirming the physicochemical and microbiological results. The fact that the type of feed had no effect on the freshness parameters studied demonstrates that total fishmeal replacement with plant protein blends in the proportions used in this work could be an excellent alternative for feed formulation in aquaculture.
- Published
- 2020
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- View/download PDF
38. Lab and Pilot-Scale Synthesis of MxOm@SiC Core–Shell Nanoparticles
- Author
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Àngela Ribes, Santiago Sánchez-Cabezas, Andy Hernández-Montoto, Luis A. Villaescusa, Elena Aznar, Ramón Martínez-Máñez, M. Dolores Marcos, M. José López-Tendero, Sarai Pradas, and Alejandro Cuenca-Bustos
- Subjects
core–shell nanoparticles ,silicon carbide covering ,sol–gel synthesis ,synthesis up-scaling ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
The addition of light ceramic particles to bulk technological materials as reinforcement to improve their mechanical properties has attracted increasing interest in the last years. The metal matrix composites obtained using nanoparticles have been reported to exhibit an improvement of their properties due to the decrease in the size of the ceramic additives to the nanoscale. Additionally, important effects such as the dispersion of the nanoparticles, wettability, and low reactivity can be controlled by the modification of the nanoparticles’ surface. In this work, we present the preparation of core−shell MxOm@SiC nanoparticles with different shell compositions. The accurate and reproducible preparation is developed both at the lab and pilot scale. The synthesis of these core−shell nanoparticles and their scale-up production are fundamental steps for their industrial use as additives in metal matrix composites and alloys. Powder X-ray diffraction and energy dispersive X-ray (EDX) coupled with scanning transmission electron microscopy (STEM) are used to corroborate the formation of the core−shell systems, whereas line scan-EDX analysis allows measuring the average shell thickness.
- Published
- 2020
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- View/download PDF
39. A versatile drug delivery system targeting senescent cells
- Author
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Daniel Muñoz‐Espín, Miguel Rovira, Irene Galiana, Cristina Giménez, Beatriz Lozano‐Torres, Marta Paez‐Ribes, Susana Llanos, Selim Chaib, Maribel Muñoz‐Martín, Alvaro C Ucero, Guillermo Garaulet, Francisca Mulero, Stephen G Dann, Todd VanArsdale, David J Shields, Andrea Bernardos, José Ramón Murguía, Ramón Martínez‐Máñez, and Manuel Serrano
- Subjects
chemotherapy ,fibrosis ,nanomedicine ,palbociclib ,senescence ,Medicine (General) ,R5-920 ,Genetics ,QH426-470 - Abstract
Abstract Senescent cells accumulate in multiple aging‐associated diseases, and eliminating these cells has recently emerged as a promising therapeutic approach. Here, we take advantage of the high lysosomal β‐galactosidase activity of senescent cells to design a drug delivery system based on the encapsulation of drugs with galacto‐oligosaccharides. We show that gal‐encapsulated fluorophores are preferentially released within senescent cells in mice. In a model of chemotherapy‐induced senescence, gal‐encapsulated cytotoxic drugs target senescent tumor cells and improve tumor xenograft regression in combination with palbociclib. Moreover, in a model of pulmonary fibrosis in mice, gal‐encapsulated cytotoxics target senescent cells, reducing collagen deposition and restoring pulmonary function. Finally, gal‐encapsulation reduces the toxic side effects of the cytotoxic drugs. Drug delivery into senescent cells opens new diagnostic and therapeutic applications for senescence‐associated disorders.
- Published
- 2018
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40. Molecular and Cellular Risk Assessment of Healthy Human Cells and Cancer Human Cells Exposed to Nanoparticles
- Author
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Edward Helal-Neto, Aline Oliveira da Silva de Barros, Roberta Saldanha-Gama, Renata Brandão-Costa, Luciana Magalhães Rebêlo Alencar, Clenilton Costa dos Santos, Ramón Martínez-Máñez, Eduardo Ricci-Junior, Frank Alexis, Verônica Morandi, Christina Barja-Fidalgo, and Ralph Santos-Oliveira
- Subjects
nanoparticles ,nanomedicine ,tumor cell ,cell culture ,primary cells ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Nanodrugs have in recent years been a subject of great debate. In 2017 alone, almost 50 nanodrugs were approved for clinical use worldwide. Despite the advantages related to nanodrugs/nanomedicine, there is still a lack of information regarding the biological safety, as the real behavior of these nanodrugs in the body. In order to better understand these aspects, in this study, we evaluated the effect of polylactic acid (PLA) nanoparticles (NPs) and magnetic core mesoporous silica nanoparticles (MMSN), of 1000 nm and 50 nm, respectively, on human cells. In this direction we evaluated the cell cycle, cytochemistry, proliferation and tubulogenesis on tumor cells lines: from melanoma (MV3), breast cancer (MCF-7, MDA-MB-213), glioma (U373MG), prostate (PC3), gastric (AGS) and colon adenocarcinoma (HT-29) and non-tumor cell lines: from human melanocyte (NGM), fibroblast (FGH) and endothelial (HUVEC), respectively. The data showed that an acute exposure to both, polymeric nanoparticles or MMSN, did not show any relevant toxic effects on neither tumor cells nor non-tumor cells, suggesting that although nanodrugs may present unrevealed aspects, under acute exposition to human cells they are harmless.
- Published
- 2019
- Full Text
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41. Mesoporous silica microparticles gated with a bulky azo derivative for the controlled release of dyes/drugs in colon
- Author
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Daniel Ferri, Pablo Gaviña, Margarita Parra, Ana M. Costero, Jamal El Haskouri, Pedro Amorós, Virginia Merino, Adrián H. Teruel, Félix Sancenón, and Ramón Martínez-Máñez
- Subjects
mesoporous silica microparticles ,gated materials ,controlled drug release ,colon targeting ,inflammatory bowel disease ,budesonide ,Science - Abstract
Mesoporous silica microparticles were prepared, loaded with the dye safranin O (M-Saf) or with the drug budesonide (M-Bud) and capped by the grafting of a bulky azo derivative. Cargo release from M-Saf at different pH values (mimicking those found in the gastrointestinal tract) in the absence or presence of sodium dithionite (a reducing agent mimicking azoreductase enzyme present in the colon) was tested. Negligible safranin O release was observed at pH 6.8 and 4.5, whereas a moderate delivery at pH 1.2 was noted and attributed to the hydrolysis of the urea bond that linked the azo derivative onto the external surface of the inorganic scaffold. Moreover, a marked release was observed when sodium dithionite was present and was ascribed to the rupture of the azo bond in the molecular gate. Budesonide release from M-Bud in the presence of sodium dithionite was also assessed by ultraviolet-visible spectroscopy and high performance liquid chromatography measurements. In addition, preliminary in vivo experiments with M-Saf carried out in mice indicated that the chemical integrity of the microparticles remained unaltered in the stomach and the small intestine, and safranin O seemed to be released in the colon.
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- 2018
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42. Urinary Metabolic Signatures Detect Recurrences in Non-Muscle Invasive Bladder Cancer
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Alba Loras, M. Carmen Martínez-Bisbal, Guillermo Quintás, Salvador Gil, Ramón Martínez-Máñez, and José Luis Ruiz-Cerdá
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bladder cancer ,recurrence prediction ,biomarker ,metabolite ,metabolomics ,metabolic pathways ,nuclear magnetic resonance ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Patients with non-muscle invasive bladder cancer (NMIBC) undergo lifelong monitoring based on repeated cystoscopy and urinary cytology due to the high recurrence rate of this tumor. Nevertheless, these techniques have some drawbacks, namely, low accuracy in detection of low-grade tumors, omission of pre-neoplastic lesions and carcinomas in situ (CIS), invasiveness, and high costs. This work aims to identify a urinary metabolomic signature of recurrence by proton Nuclear Magnetic Resonance (1H NMR) spectroscopy for the follow-up of NMIBC patients. To do this, changes in the urinary metabolome before and after transurethral resection (TUR) of tumors are analyzed and a Partial Least Square Discriminant Analysis (PLS-DA) model is developed. The usefulness of this discriminant model for the detection of tumor recurrences is assessed using a cohort of patients undergoing monitoring. The trajectories of the metabolomic profile in the follow-up period provide a negative predictive value of 92.7% in the sample classification. Pathway analyses show taurine, alanine, aspartate, glutamate, and phenylalanine perturbed metabolism associated with NMIBC. These results highlight the potential of 1H NMR metabolomics to detect bladder cancer (BC) recurrences through a non-invasive approach.
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- 2019
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43. Integrative Metabolomic and Transcriptomic Analysis for the Study of Bladder Cancer
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Alba Loras, Cristian Suárez-Cabrera, M. Carmen Martínez-Bisbal, Guillermo Quintás, Jesús M. Paramio, Ramón Martínez-Máñez, Salvador Gil, and José Luis Ruiz-Cerdá
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cancer biomarkers ,bladder cancer ,metabolomics ,transcriptomics ,metabolic pathways ,tumor metabolome ,cancer metabolic reprogramming ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Metabolism reprogramming is considered a hallmark of cancer. The study of bladder cancer (BC) metabolism could be the key to developing new strategies for diagnosis and therapy. This work aimed to identify tissue and urinary metabolic signatures as biomarkers of BC and get further insight into BC tumor biology through the study of gene-metabolite networks and the integration of metabolomics and transcriptomics data. BC and control tissue samples (n = 44) from the same patients were analyzed by High-Resolution Magic Angle Spinning Nuclear Magnetic Resonance and microarrays techniques. Besides, urinary profiling study (n = 35) was performed in the same patients to identify a metabolomic profile, linked with BC tissue hallmarks, as a potential non-invasive approach for BC diagnosis. The metabolic profile allowed for the classification of BC tissue samples with a sensitivity and specificity of 100%. The most discriminant metabolites for BC tissue samples reflected alterations in amino acids, glutathione, and taurine metabolic pathways. Transcriptomic data supported metabolomic results and revealed a predominant downregulation of metabolic genes belonging to phosphorylative oxidation, tricarboxylic acid cycle, and amino acid metabolism. The urinary profiling study showed a relation with taurine and other amino acids perturbed pathways observed in BC tissue samples, and classified BC from non-tumor urine samples with good sensitivities (91%) and specificities (77%). This urinary profile could be used as a non-invasive tool for BC diagnosis and follow-up.
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- 2019
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44. Electrospun Antimicrobial Films of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Containing Eugenol Essential Oil Encapsulated in Mesoporous Silica Nanoparticles
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Beatriz Melendez-Rodriguez, Kelly J. Figueroa-Lopez, Andrea Bernardos, Ramón Martínez-Máñez, Luis Cabedo, Sergio Torres-Giner, and Jose M. Lagaron
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PHBV ,MCM-41 ,eugenol ,antimicrobial properties ,active packaging ,Chemistry ,QD1-999 - Abstract
The main goal of this study was to develop poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) films with long-term antimicrobial capacity of interest in food packaging applications. To this end, eugenol was first highly efficiently encapsulated at 50 wt.-% in the pores of mesoporous silica nanoparticles by vapor adsorption. The eugenol-containing nanoparticles were then loaded in the 2.5⁻20 wt.-% range into PHBV by electrospinning and the resultant electrospun composite fibers were annealed at 155 °C to produce continuous films. The characterization showed that the PHBV films filled with mesoporous silica nanoparticles containing eugenol present sufficient thermal resistance and enhanced mechanical strength and barrier performance to water vapor and limonene. The antimicrobial activity of the films was also evaluated against foodborne bacteria for 15 days in open vs. closed conditions in order to simulate real packaging conditions. The electrospun PHBV films with loadings above 10 wt.-% of mesoporous silica nanoparticles containing eugenol successfully inhibited the bacterial growth, whereas the active films stored in hermetically closed systems increased their antimicrobial activity after 15 days due to the volatile portion accumulated in the system’s headspace and the sustained release capacity of the films. The resultant biopolymer films are, therefore, potential candidates to be applied in active food packaging applications to provide shelf life extension and food safety.
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- 2019
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45. Anchoring Gated Mesoporous Silica Particles to Ethylene Vinyl Alcohol Films for Smart Packaging Applications
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Virginia Muriel-Galet, Édgar Pérez-Esteve, María Ruiz-Rico, Ramón Martínez-Máñez, José Manuel Barat, Pilar Hernández-Muñoz, and Rafael Gavara
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MCM-41 ,gated mesoporous silica particles ,EVOH films ,anchorage on film surface ,active packaging ,pH-mediated delivery ,Chemistry ,QD1-999 - Abstract
This work is a proof of concept for the design of active packaging materials based on the anchorage of gated mesoporous silica particles with a pH triggering mechanism to a packaging film surface. Mesoporous silica micro- and nanoparticles were loaded with rhodamine B and functionalized with N-(3-trimethoxysilylpropyl)diethylenetriamine. This simple system allows regulation of cargo delivery as a function of the pH of the environment. In parallel, poly(ethylene-co-vinyl alcohol) films, EVOH 32 and EVOH 44, were ultraviolet (UV) irradiated to convert hydroxyl moieties of the polymer chains into –COOH functional groups. The highest COOH surface concentration was obtained for EVOH 32 after 15 min of UV irradiation. Anchoring of the gated mesoporous particles to the films was carried out successfully at pH 3 and pH 5. Mesoporous particles were distributed homogeneously throughout the film surface and in greater concentration for the EVOH 32 films. Films with the anchored particles were exposed to two liquid media simulating acidic food and neutral food. The films released the cargo at neutral pH but kept the dye locked at acidic pH. The best results were obtained for EVOH 32 irradiated for 15 min, treated for particle attachment at pH 3, and with mesoporous silica nanoparticles. This opens the possibility of designing active materials loaded with antimicrobials, antioxidants, or aromatic compounds, which are released when the pH of the product approaches neutrality, as occurs, for instance, with the release of biogenic amines from fresh food products.
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- 2018
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46. Glyphosate Detection by Means of a Voltammetric Electronic Tongue and Discrimination of Potential Interferents
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Javier Ibáñez-Civera, Eduardo García-Breijo, Ramón Martínez-Máñez, Luís Gil, Nicolas Laguarda-Miro, Miguel Alcañiz, Juan Soto, Román Bataller, and Inmaculada Campos
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glyphosate ,electronic tongue ,rotating disk electrodes ,PLS ,Chemical technology ,TP1-1185 - Abstract
A new electronic tongue to monitor the presence of glyphosate (a non-selective systemic herbicide) has been developed. It is based on pulse voltammetry and consists in an array of three working electrodes (Pt, Co and Cu) encapsulated on a methacrylate cylinder. The electrochemical response of the sensing array was characteristic of the presence of glyphosate in buffered water (phosphate buffer 0.1 mol·dm−3, pH 6.7). Rotating disc electrode (RDE) studies were carried out with Pt, Co and Cu electrodes in water at room temperature and at pH 6.7 using 0.1 mol·dm−3 of phosphate as a buffer. In the presence of glyphosate, the corrosion current of the Cu and Co electrodes increased significantly, probably due to the formation of Cu2+ or Co2+ complexes. The pulse array waveform for the voltammetric tongue was designed by taking into account some of the redox processes observed in the electrochemical studies. The PCA statistical analysis required four dimensions to explain 95% of variance. Moreover, a two-dimensional representation of the two principal components differentiated the water mixtures containing glyphosate. Furthermore, the PLS statistical analyses allowed the creation of a model to correlate the electrochemical response of the electrodes with glyphosate concentrations, even in the presence of potential interferents such as humic acids and Ca2+. The system offers a PLS prediction model for glyphosate detection with values of 098, −2.3 × 10−5 and 0.94 for the slope, the intercept and the regression coefficient, respectively, which is in agreement with the good fit between the predicted and measured concentrations. The results suggest the feasibility of this system to help develop electronic tongues for glyphosate detection.
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- 2012
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47. Quantitative Determination of Spring Water Quality Parameters via Electronic Tongue
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Noèlia Carbó, Javier López Carrero, F. Javier Garcia-Castillo, Isabel Tormos, Estela Olivas, Elisa Folch, Miguel Alcañiz Fillol, Juan Soto, Ramón Martínez-Máñez, and M. Carmen Martínez-Bisbal
- Subjects
spring water ,electronic voltammetric tongue ,water quality control ,partial least squares ,Chemical technology ,TP1-1185 - Abstract
The use of a voltammetric electronic tongue for the quantitative analysis of quality parameters in spring water is proposed here. The electronic voltammetric tongue consisted of a set of four noble electrodes (iridium, rhodium, platinum, and gold) housed inside a stainless steel cylinder. These noble metals have a high durability and are not demanding for maintenance, features required for the development of future automated equipment. A pulse voltammetry study was conducted in 83 spring water samples to determine concentrations of nitrate (range: 6.9–115 mg/L), sulfate (32–472 mg/L), fluoride (0.08–0.26 mg/L), chloride (17–190 mg/L), and sodium (11–94 mg/L) as well as pH (7.3–7.8). These parameters were also determined by routine analytical methods in spring water samples. A partial least squares (PLS) analysis was run to obtain a model to predict these parameter. Orthogonal signal correction (OSC) was applied in the preprocessing step. Calibration (67%) and validation (33%) sets were selected randomly. The electronic tongue showed good predictive power to determine the concentrations of nitrate, sulfate, chloride, and sodium as well as pH and displayed a lower R2 and slope in the validation set for fluoride. Nitrate and fluoride concentrations were estimated with errors lower than 15%, whereas chloride, sulfate, and sodium concentrations as well as pH were estimated with errors below 10%.
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- 2017
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48. Development of a Textile Nanocomposite as Naked Eye Indicator of the Exposition to Strong Acids
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Isabel Pallás, Maria D. Marcos, Ramón Martínez-Máñez, and Jose V. Ros-Lis
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sensor ,indicator ,mesoporous material ,colour ,strong acid ,textile ,Chemical technology ,TP1-1185 - Abstract
Chemical burns, mainly produced by acids, are a topic of concern. A new sensing material for the detection of strong acids able to be incorporated into textiles has been developed. The material is prepared by the covalent attachment of 2,2′,4,4′,4″-pentamethoxy triphenyl methanol to a mesoporous material which further is included in a nitro resin to obtain a colourless composite. The response of this composite to diverse acid solutions was tested showing the appearance of an intense purple colour (with a colour difference higher than 160) that can be monitored by the naked eye or could be easily digitised to feed an instrumental sensor. Reversibility and resistance to washing cycles were studied with positive results. Finally, the response of the sensing composite to acid vapours was assayed, observing a colour change similar to that found in solution.
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- 2017
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49. Rapid Biosynthesis of Silver Nanoparticles Using Pepino (Solanum muricatum) Leaf Extract and Their Cytotoxicity on HeLa Cells
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Mónica Gorbe, Ravishankar Bhat, Elena Aznar, Félix Sancenón, M. Dolores Marcos, F. Javier Herraiz, Jaime Prohens, Abbaraju Venkataraman, and Ramón Martínez-Máñez
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biosynthesis ,silver nanoparticles ,Solanum muricatum ,microwave irradiation ,cytotoxic studies ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Within nanotechnology, gold and silver nanostructures have unique physical, chemical, and electronic properties [1,2], which make them suitable for a number of applications. Moreover, biosynthetic methods are considered to be a safer alternative to conventional physicochemical procedures for both the environmental and biomedical applications, due to their eco-friendly nature and the avoidance of toxic chemicals in the synthesis. For this reason, employing bio routes in the synthesis of functionalized silver nanoparticles (FAgNP) have gained importance recently in this field. In the present study, we report the rapid synthesis of FAgNP through the extract of pepino (Solanum muricatum) leaves and employing microwave oven irradiation. The core-shell globular morphology and characterization of the different shaped and sized FAgNP, with a core of 20–50 nm of diameter is established using the UV-Visible spectroscopy (UV-vis), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and Zeta potential and dynamic light scanning (DLS) studies. Moreover, cytotoxic studies employing HeLa (human cervix carcinoma) cells were undertaken to understand FAgNP interactions with cells. HeLa cells showed significant dose dependent antiproliferative activity in the presence of FAgNP at relatively low concentrations. The calculated IC50 value was 37.5 µg/mL, similar to others obtained for FAgNPs against HeLa cells.
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- 2016
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50. Channel Responses for the Molecule Release From Spherical Homogeneous Matrix Carriers.
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Maximilian Schafer, Yolanda Salinas, Alexander Ruderer, Franz Enzenhofer, Oliver Brüggemann, Ramón Martínez-Máñez, Rudolf Rabenstein, Robert Schober, and Werner Haselmayr
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- 2022
- Full Text
- View/download PDF
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