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Background: Drug combination therapy is preferred over monotherapy in clinical research to improve therapeutic effects. Developing a new nanodelivery system for cancer drugs can reduce side effects and provide several advantages, including matched pharmacokinetics and potential synergistic activity. This study aimed to examine and determine the efficiency of the gemini surfactants (GSs) as a pH-sensitive polymeric carrier and cell-penetrating agent in cancer cells to achieve dual drug delivery and synergistic effects of curcumin (Cur) combined with tamoxifen citrate (TMX) in the treatment of MCF-7 and MDA-MB-231 human BC cell lines., Methods: The synthesized NPs were self-assembled using a modified nanoprecipitation method. The functional groups and crystalline form of the nanoformulation were examined by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and dynamic light scattering (DLS) used to assess zeta potential and particle size, and the morphological analysis determined by transmission electron microscopy (TEM). The anticancer effect was evaluated through an in vitro cytotoxicity MTT assay, flow cytometry analysis, and apoptosis analysis performed for mechanism investigation., Results: The tailored NPs were developed with a size of 252.3 ± 24.6 nm and zeta potential of 18.2 ± 4.4 mV capable of crossing the membrane of cancer cells. The drug loading and release efficacy assessment showed that the loading of TMX and Cur were 93.84% ± 1.95% and 90.18% ± 0.56%, respectively. In addition, the drug release was more controlled and slower than the free state. Polymeric nanocarriers improved controlled drug release 72.19 ± 2.72% of Tmx and 55.50 ± 2.86% of Cur were released from the Tmx-Cur-Gs NPs after 72 h at pH = 5.5. This confirms the positive effect of polymeric nanocarriers on the controlled drug release mechanism. moreover, the toxicity test showed that combination-drug delivery was much more greater than single-drug delivery in MCF-7 and MDA-MB-231 cell lines. Cellular imaging showed excellent internalization of TMX-Cur-GS NPs in both MCF-7 and MDA-MB-231 cells and synergistic anticancer effects, with combination indices of 0.561 and 0.353, respectively., Conclusion: The combined drug delivery system had a greater toxic effect on cell lines than single-drug delivery. The synergistic effect of TMX and Cur with decreasing inhibitory concentrations could be a more promising system for BC-targeted therapy using GS NPs., (© 2024. The Author(s).)

'Active targeting' refers to modifying a nanocarrier's surface with targeting ligands. This study introduced an efficient approach for immobilizing imidazole-based drugs onto the metallated-porphyrin complex within the porphysome nanocarrier. To enhance cellular and bacterial uptake, a Ni-porphyrin with a fatty acid tail was synthesized and placed in the bilayer center of DPPC, facilitating receptor-mediated endocytosis. The Ni-porphyrin in the head group of the Ni-porphyrin-tail was placed superficially in the polar region of the membrane. Spherical unilamellar vesicle formation (DPPC: Ni-porphyrin-tail 4:1 mole ratio), as metallo-porphysome, was achieved through supramolecular self-assembly in an aqueous buffer. These vesicles exhibited a diameter of 279 ± 7 nm and a zeta potential of -15.3 ± 2.5 mV, showcasing their unique cytocompatibility. Nitroimidazole was decorated on the surface of metallo-porphysomes and pistachio green hull extract (PGHE) was loaded into the carrier for synergistic activity against ( E. coli ) and ( S. aureus ) bacteria strains. The physicochemical properties of Nitroimidazole-porphysome-PGHE, including size, zeta potential, morphology, loading efficiency, and release profile under various pH and temperature conditions in simulated gastrointestinal fluids were characterized. This combination therapy prevented bacterial cell attachment and biofilm formation in Caco-2 cells, as colon epithelial cells. The remarkable benefit of this system is that it does not affect cell viability even at 0.5 mg/ml. This study demonstrates the potential of a new co-delivery system using biocompatible metallo-porphysomes to decrease bacterial infections.

The oral formulation design for colon-specific drug delivery brings some therapeutic benefits in the ulcerative colitis treatment. We recently reported the specific delivery of hemoglobin nanoparticles-conjugating 5-aminosalicylic acid (5-ASA-HbNPs) to the inflamed site. In the current study, the therapeutic effect of the 5-ASA-HbNPs formulation was confirmed in vivo. This evaluation of 5-ASA-HbNPs not only shows longer colonic retention time due to adhesive properties, also provides full support for it as compared with free 5-ASA. It was considered as a suitable bio-adhesive nanoparticle with mucoadhesive property to pass through the mucus layer and accumulate into the mucosa. In UC model mice, a two-fold decrease in the disease activity indexes and colon weight/length ratios was significantly observed in the group treated with 5-ASA-HbNPs. This group received one percent of the standard dosage of 5-ASA (50 μg/kg), while, a similar result was observed for a significant amount of free 5-ASA (5 mg/kg). Furthermore, microscopic images of histological sections of the extracted colons demonstrated that the 5-ASA-HbNPs and 5-ASA groups displayed instances of inflammatory damage within the colon. However, in comparison to the colitis group, the extent of this damage was relatively moderate, suggesting 5-ASA-HbNPs improved therapeutic efficacy with the lower dosage form., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 American Pharmacists Association. Published by Elsevier Inc. All rights reserved.)

The immobilization of proteins on the surface of carriers is challenging due to the loss of protein structure and function in this process. Here, we report the development of the protein immobilization on the surface of the metallated-porphyrin complex in the porphysome nanocarrier. The conjugated Ni-porphyrin to fatty acid (as a tail) has been synthesized and independently placed at the depth of the bilayer center of Dipalmitoylphosphatidylcholine (DPPC) in which the Ni-porphyrin was at the polar region of the membrane and is thus superficial. This porphysome (DPPC: Ni-porphyrin, 4 : 1 mole ratio) was formed by supramolecular self-assembly with a diameter of 173±7 nm and zeta potential -8.5±3.4 mv, which exhibited no significant toxicity at the experimental concentrations and acceptable cellular uptake on MCF-7 cells. The physicochemical properties and specific protein binding sites of the firefly luciferase as a model protein into the porphysome (1 : 2 mole ratio) show the conjugation efficiency about 80 % and the conformation of protein was completely maintained. Furthermore, bioluminescence assay and SDS-PAGE confirmed the preservation of protein function. The stabilized platform of porphyrin-lipid structure can potentially improve the efficacy of protein functionality for a particular display, shifting porphysomes from a simple carrier to a therapeutic agent., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Glucosamine (Glu) is a cartilage and joint fluid matrix precursor that modulates osteoarthritic joint changes. To improve the enzymatic stability, glucosamine was developed into nanoglucosamine by the ionic gelation method through sodium tripolyphosphate (TPP) as cross-linking agent. The optimized mass ratio of Glu:TPP was (3:1) with the particle size 163 ± 25 nm and surface charge -5 mV. Then Sinapic acid (SA) as a natural phenolic acid with strong antioxidant and antimicrobial activities has been grafted onto glucosamine nanoparticles (GluNPs) with grafting efficiency (73 ± 6 %). The covalent insertion of SA was confirmed by UV-Vis, FTIR, 1 HNMR, XRD, and FESEM analyses and the other physicochemical properties were also characterized. SA-g-GluNPs showed spherical shape with a mean diameter of 255 ± 20 nm and zeta potential +16 mV. The in vitro release profile of SA-g-GluNPs exhibited the sustained and pH-dependent drug release property. SA-g-GluNPs had a more pronounced effect on reducing the elevated levels of LPS-induced oxidative stress and pro-inflammatory cytokines than free SA in the human chondrocyte C28/I2 cell line. Furthermore, the antibacterial properties against E. coli and S. aureus were also improved by SA-g-GluNPs. This study demonstrated the potential of phenolic acid grafted GluNPs in therapeutic drug applications for chondroprotection and food industries., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Mental disorders have a high prevalence and significant burden among all health conditions across the world and in Iran. Therefore, some targets in the field of mental health and substance and alcohol use prevention have been included in the National Action Plan for Prevention and Control of Non-communicable Diseases and Related Risk Factors. Methods: Keeping in mind the key priorities, important strategies have been considered for attaining the main targets in this field. These strategies fall under four categories of governance, prevention and reduction of risk factors, health care, and surveillance, and monitoring and evaluation strategies. Conclusion: The success of mental health and substance and alcohol use prevention programs in Iran can be partly related to the evidence-based approach adopted and also to the commitment of high-rank officials of the Ministry of Health and Medical Education to the principal strategy of increasing access to the general population to basic mental health services, among all other non-communicable diseases., (© 2022 Iran University of Medical Sciences.)

Circulating tumor cells (CTCs), secreted from primary and metastatic malignancies, hold a wealth of essential diagnostic and prognostic data for multiple cancers. Significantly, the information contained within these cells may hold the key to understanding cancer metastasis, both individually and fundamentally. Accordingly, developing ways to identify, isolate and interrogate CTCs plays an essential role in modern cancer research. Unfortunately, CTCs are typically present in the blood in vanishingly low titers and mixed with other blood components, making their isolation and analysis extremely challenging. Herein, we report the design, fabrication and optimization of a microfluidic device capable of automatically isolating CTCs from whole blood. This is achieved in two steps, via the passive viscoelastic separation of CTCs and white blood cells (WBCs) from red blood cells (RBCs), and subsequent active magnetophoretic separation of CTCs from WBCs. We detail the specific geometries required to balance the elastic and inertial forces required for successful passive separation of RBCs, and the use of computational fluid dynamics (CFD) to optimize active magnetophoretic separation. We subsequently describe the use of magnetic biosilica frustules, extracted from Chaetoceros sp. diatoms, to fluorescently tag CTCs and facilitate magnetic isolation. Finally, we use our microfluidic platform to separate HepG2-derived CTCs from whole blood, demonstrating exceptional CTC recovery (94.6%) and purity (89.7%)., (Copyright 2022 Rashin Mohammadi, Mohammad Asghari, Monika Colombo, Zahra Vaezi , Daniel Richards, Stavros Stavrakis, Hossein Naderi-Manesh, Andrew deMello. License: This work is licensed under a Creative Commons Attribution 4.0 International License.)

This review discusses recent advances and the reported strategies over the last ten years on the use of carbon-based quantum dots (QDs), including carbon dots (CDs), graphene quantum dots (GQDs), and polymer dots (PDs) in the design of fluorescence imaging and biosensing system for early diagnosis of cancers. Besides, this study comprehensively reports the latest developments in these years in the fluorescence imaging (FI) area with special attention to carbon-based QDs that take advantage of the excellent properties offered by these zero-dimensional (0D) nanomaterials as fluorescent tags. The most remarkable advantages of these carbon nanomaterials in the development of fluorescence sensing and imaging strategies compared to the conventional dyes arise from sharp emission spectra, long photostability, low-cost synthesis, reliability, reproducibility, high fluorescent intensity, and high surface functional groups such as carboxyl and amide, which impart better solubility in many solvents and aqueous media and facilitate their easy functionalization with biological species. The final section discusses the main challenges to be met to take full advantage of these properties in fluorescence bio-sensing and imaging as well as the possible future trends in this field based on the great advances that have occurred in recent years., (Copyright © 2022 Elsevier B.V. All rights reserved.)

A colonic drug delivery system was developed to specifically deliver 5-aminosalicylic acid (5-ASA) to the inflamed site by conjugating with hemoglobin nanoparticles (HbNPs). The 5-ASA-HbNPs (eight 5-ASA molecules per Hb molecule) with the size of 220 nm and zeta potential of -14.6 mV is a tailored nanoparticle able to pass through the mucus layer. The 5-ASA-HbNPs do not undergo chemical and enzymatic hydrolysis in the simulated gastrointestinal fluids over 6 h. Significantly higher cellular uptakes and prolonged release was seen for the 5-ASA-HbNPs in Caco-2 cells, compared to free 5-ASA over 72 h. In addition, 5-ASA-HbNPs revealed similar therapeutic effectiveness with free 5-ASA against tumor necrosis factor and showed less inhibitory concentration (IC50) for myeloperoxidase enzyme activity. In vivo imaging of mouse demonstrated the localization of drug in the descending colon after oral administration and about 15% of the administered dose was recovered as 5-ASA from urine in 6 h. The use of these nanoparticles with the mucus adhesion properties and permeability to intestinal epithelial cells can be a good candidate with potential application in the colonic drug delivery field., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Pseudomonas aeruginosa is the most common pathogen that causes chronic lung infections and recurrence of the disease in cystic fibrosis patients by hiding inside cells and biofilm matrix. Herein, we developed gentamicin and curcumin-loaded lipid-polymer hybrid nanoparticle- (termed CG-HNPs) to evaluate in vitro activities against biofilm-embedded P. aeruginosa and compared with lipid nanoparticles containing the same drugs (CG-Lip). The nanoparticles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), fluorescence spectroscopy, and ultraviolet-visible (UV-vis) spectroscopy, which demonstrated that HNPs with a diameter of approximately 340 nm were uniform. The optimal CG-HNPs formulation illustrated high encapsulation (∼70%) and controlled release characteristics (gradually released in 72 h). The antibacterial activities of generated nanoparticles are maintained against planktonic and biofilm bacteria and it is effective in damage established biofilms. Besides, HNPs were biocompatible and nontoxic to J774 and HFF cell lines and uptake by the macrophages (J774), which facilitated the killing of intracellular bacteria in macrophages. These results introduced CG-HNPs as a promising antibacterial agent for the treatment of chronic infections and intracellular bacteria due to excellent antibacterial activity.

Imidazolium-based ionic liquid functionalized PEGylated mesoporous silica nanoparticles MCM-41 (denoted as [ImIL-PEGylated@MCM-41] NPs) is synthesized and evaluated as an efficient and reliable pH-sensitive nano-carrier for controlled release of cationic Lapatinib (Lap) drug. This nano-DDS was fully characterized by dynamic light scattering, scanning electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, N 2 adsorption-desorption measurement, and differential scanning calorimeter. Furthermore, the drug loading content and in-vitro drug release profile were studied. The entrapment and loading efficiency of the optimized formulation for Lap were 91 ± 2.0% and 32.21 ± 2.70%, respectively. The results of cytotoxicity assay demonstrated that ImIL-PEG@MCM-41 has no significant toxicity on both cancerous and normal cell lines and the anticancer activity of Lap@ImIL-PEG@MCM-41 was comparable to free drug in case of human breast cells (SKBR3) and human embryonic kidney 293 cells (HEK-293). Meanwhile, three-dimensional (3D) cell culture was performed by multicellular tumor spheroids for understanding of cell response to drugs in physiologically 3D microenvironments. The results of Lap@ImIL-PEG@MCM-41 uptake during 48 hours showed a gradual release of the Lap through the multicellular tumor spheroids. This showed that the pH-responsive controlled release of Lapatinib leads to the satisfactory results in the in vitro breast cancer therapy.

A new method based on fluorescent probe of iron quantum cluster has been proposed for rapid detection of Escherichia coli (E. coli). The iron quantum cluster was synthesized using hemoglobin as both a source of iron and a protective agent (Hb-FeQCs). The investigation of the sensitivity of Hb-FeQCs towards metal ions showed a highly selective turn off fluorescence for Cu 2+ . It suggests that Cu 2+ can induce fluorescence quenching by binding to amino acids of Hb. The ability of E. coli bacteria to capture and reduce of Cu ions caused to efficient recovery of the fluorescence of Hb-FeQCs from Cu 2+ -caused quenching. This probe has a satisfactorily linear range of 0.35-35 μM for Cu 2+ under the optimal iron quantum cluster concentration (500 μg/mL) with an 85 nM detection limit. Rapid and facile detection of E.coli bacteria with the limit of detection around 8.3 × 10 3  CFU/mL was successfully achieved in the artificially contaminated urine, tap water, and DMEM samples within 30 min. The fluorescence recovery was investigated by different types of bacteria and only E. coli revealed 56% recovery which related to its capability to Cu 2+ reduction and the great potential of the fluorescent probe for rapid detection of pathogenic E. coli bacteria. Furthermore, the Hb-FeQCs can detect E. coli bacteria in an infected urine sample by retrieving up to 74% of its fluorescence which is helpful to accelerate the diagnosis and treatment of urinary tract infection (UTI)., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Allergic bronchopulmonary aspergillosis (ABPA) is an eosinophilic pulmonary disorder caused by a hypersensitivity reaction to Aspergillus fumigatus that manifests with uncontrolled asthma, peripheral blood eosinophilia, and radiological findings, such as mucus plugging. Early diagnosis and proper treatment of ABPA are essential to prevent irreversible lung damage such as pulmonary fibrosis and bronchiectasis and improve the quality of life of patients. Beside inhaled medication for asthma, anti-inflammatory agents (i.e., systemic glucocorticoids) and antifungal agents are the mainstay treatment of ABPA. The goal of therapy using glucocorticoids and antifungal agents is to suppress the immune hyperreactivity to A. fumigatus and attenuate the fungal burden. Since the systemic glucocorticoid therapy may lead to serious adverse effects including osteoporosis, avascular necrosis, myopathy, cushingoid appearance, hypertension, insomnia, and increased risk of infection, a glucocorticoid-sparing agent could be considered. Mepolizumab is a humanized monoclonal antibody that binds to interleukin-5, which is the key mediator for eosinophil differentiation, activation, migration, and survival. We review eight cases of ABPA treated successfully with mepolizumab. Treatment with mepolizumab was not restricted to the total immunoglobulin E level, the limiting factor for omalizumab in ABPA. In addition, mepolizumab therapy improved forced expiratory volume in one second, radiological findings, and patient quality of life., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2020, Tolebeyan et al.)

Template-mediated self-assembly synthesis has produced a diverse range of biomimetic materials with unique physicochemical properties. Here, we fabricated novel fluorescent three-dimensional (3-D) hydroxyapatite (HAP) nanorod-assembled microspheres using iron quantum cluster (FeQC) as a hybrid template, containing three organic components: hemoglobin chains, piperidine, and iron clusters. The material characterization indicated that the synthesized HAP possessed a uniform rod-like morphology, ordered 3-D architecture, high crystallinity, self-activated fluorescence, and remarkable photostability. Our study proposed that this FeQC template is a promising regulating agent to fabricate fluorescent self-assembled HAP microspheres with a controlled morphology. The effect of HAP on stem cell fate and their osteogenic differentiation was investigated by culturing human bone marrow-derived mesenchymal stromal/stem cells (BMSCs) with HAP microspheres. Significant increases in collagen matrix production and gene expression of osteogenic markers, including osteocalcin (OCN), Runt-related transcription factor 2 (Runx2), bone sialoprotein (BSP) and alkaline phosphatase (ALP), were observed compared to the controls after 21 days of culture. Taken together, our data suggest that synthetic HAP nanorod-assembled microspheres represent a promising new biomaterial which exhibits enhanced fluorescent properties and osteoinductive effects on human BMSCs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The ability to identify and enrich target cells can play a significant role in biosensing in general. For the separation of rare cells; a biosilica structure was extracted from "Chaetoceros sp." diatoms as a novel natural source of mesoporous materials. These diatoms had special optical capabilities, especially in fluorescence emission. Biosilica surfaces of Chaetoceros sp. were chemically modified by iron oxide nanoparticles resulting in diatom silica magnetic particles functionalized with Trastuzumab antibody to separate the breast cancer cells from normal cells. The fully characterization of magnetic biosilica structure were studied by various spectroscopic techniques. The magnetic diatom conjugated with antibody displays strong absorption and two main types of fluorescence emission with peaks centered at 493 and 650 nm (photo-excited at 405 nm). As in vitro study, SKBR3 cells (HER2 positive cells) were selectively targeted and separated with this magnetic diatom structure from the mix of HER2 negative cells using a magnetic field. These results show that Chaetoceros silica shells are promising eco-friendly biomaterials suitable for biosensing chip and the targeted delivery of drugs to the specific sites., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Microfluidics cell-based assays require strong cell-substrate adhesion for cell viability, proliferation, and differentiation. The intrinsic properties of PDMS, a commonly used polymer in microfluidics systems, regarding cell-substrate interactions have limited its application for microfluidics cell-based assays. Various attempts by previous researchers, such as chemical modification, plasma-treatment, and protein-coating of PDMS revealed some improvements. These strategies are often reversible, time-consuming, short-lived with either cell aggregates formation, not cost-effective as well as not user- and eco-friendly too. To address these challenges, cell-surface interaction has been tuned by the modification of PDMS doped with different biocompatible nanomaterials. Gold nanowires (AuNWs), superparamagnetic iron oxide nanoparticles (SPIONs), graphene oxide sheets (GO), and graphene quantum dot (GQD) have already been coupled to PDMS as an alternative biomaterial enabling easy and straightforward integration during microfluidic fabrication. The synthesized nanoparticles were characterized by corresponding methods. Physical cues of the nanostructured substrates such as Young's modulus, surface roughness, and nanotopology have been carried out using atomic force microscopy (AFM). Initial biocompatibility assessment of the nanocomposites using human amniotic mesenchymal stem cells (hAMSCs) showed comparable cell viabilities among all nanostructured PDMS composites. Finally, osteogenic stem cell differentiation demonstrated an improved differentiation rate inside microfluidic devices. The results revealed that the presence of nanomaterials affected a 5- to 10-fold increase in surface roughness. In addition, the results showed enhancement of cell proliferation from 30% (pristine PDMS) to 85% (nano-modified scaffolds containing AuNWs and SPIONs), calcification from 60% (pristine PDMS) to 95% (PDMS/AuNWs), and cell surface marker expression from 40% in PDMS to 77% in SPION- and AuNWs-PDMS scaffolds at 14 day. Our results suggest that nanostructured composites have a very high potential for stem cell studies and future therapies.

Host defense peptides selectively kill bacterial and cancer cells (including those that are drug-resistant) by perturbing the permeability of their membranes, without being significantly toxic to the host. Coulombic interactions between these cationic and amphipathic peptides and the negatively charged membranes of pathogenic cells contribute to the selective toxicity. However, a positive charge is not sufficient for selectivity, which can be achieved only by a finely tuned balance of electrostatic and hydrophobic driving forces. A common property of amphipathic peptides is the formation of aggregated structures in solution, but the role of this phenomenon in peptide activity and selectivity has received limited attention. Our data on the anticancer peptide killerFLIP demonstrate that aggregation strongly increases peptide selectivity, by reducing the effective peptide hydrophobicity and thus the affinity towards membranes composed of neutral lipids (like the outer layer of healthy eukaryotic cell membranes). Aggregation is therefore a useful tool to modulate the selectivity of membrane active peptides and peptidomimetics., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The endostatin protein is a potent inhibitor of angiogenesis and tumor growth. The anti-angiogenic and antitumor properties of full-length endostatin can be mimicked by its N-terminal segment, including residues 1-27. Therefore, our previous studies have shown that a mutant N-terminal peptide which the Zn-binding loop was replaced by a disulfide loop (referred to as the ES-SS peptide) has preserved antiangiogenic and antitumor properties compared to the native peptide. To increase stability and plasma half-life of the ES-SS peptide, the nano-sized liposomal formulations of the peptide with different ratio of phosphocholine (PC) were synthesized. The liposomal peptide formulations possessed an average size of around 100 nm with (-4 to -36 mv) in zeta potential. The encapsulation efficiency of the ES-SS peptide was in the range of 24-54% with different lipid: peptide molar ratios. In vitro release of the peptide from liposomes indicated a complete peptide release after 7 days. Cytotoxicity assay was evaluated using the human umbilical vein endothelial cells (HUVECs) for various concentrations of the liposomal peptide. The results depicted the gradual release of the peptide through liposomes. By comparing with the free peptide, the liposomal peptide formulations have indicated higher cell viability with IC 50 value about 0.1 μM. The peptide-liposome interactions, as well as the peptide effect on the liposome structure, were also investigated through coarse-grained molecular dynamics (CG-MD) simulation. The results revealed that the peptides were assembled in the hydrophilic core of the liposome. The peptide behavior in liposome can stabilize the liposome structure and be a response to the observed low peptide release rate. The investigation is promising for designing a liposome-based anti-angiogenesis peptide delivery system., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Graphene quantum dots (GQDs) represent a new generation of graphene-based nanomaterials with enormous potential for use and development of a variety of biomedical applications. However, up to now little studies have investigated the impact of GQDs on human health in case of exposure. GQDs were synthesized from citric acid as carbon precursor by hydrothermal treatment at 160 °C for 4 h. The synthesized GQDs showed strong blue emission under UV-Irradiation with fluorescence quantum yield of 9.8%. The obtained GQDs were further carbonized, activated and functionalized by nitric acid vapor method. Nitrogen adsorption/desorption isotherms were used to analyze the surface area and porous structures of GQDs. The results revealed that compared to GQDs, the specific surface area of functionalized graphene quantum dots (fGQDs) has been increased from 0.0667 to 2.5747 m 2 /g and pore structures have been enhanced significantly. The potential cytotoxic effect of GQDs, fGQDs and GO suspensions was evaluated on HFF cell line using MTT assays and flow cytometry method after 24 h incubation. We have for the first time demonstrated that by carbonization, activation and functionalization of GQDs they still showed cytocompatible properties. We observed excellent biocompatibility of GQDs and fGQDs at low concentrations. Moreover, the results suggested that modification of GQDs yields product suspensions with high surface area, enhanced pore volume and loading capacities. Thus, fGQDs represent an attractive candidate for further use in drug delivery systems and bio-imaging application., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Hydrogen peroxide (H 2 O 2 ) is one of the main source of oxidative stress and a typical marker of reactive oxygen species (ROS)-associated diseases. Therefore, selective detection and scavenging of overproduced H 2 O 2 provide enormous benefits to the successful treatment of ROS-related diseases. The authors took advantage of this property to detect cancer cells using chemiluminescent peroxyoxalate reaction. Here, a new contrast agent presented for hydrogen peroxide, termed peroxyoxalate liposomes, which detect hydrogen peroxide through chemiluminescence reaction, and have the physical/chemical properties needed for imaging applications. The peroxyoxalate liposomes are composed of Bis (2, 4, 6-trichlorphenyl) oxalate (TCPO) and curcumin as fluorophore. Experimental factors such as TCPO, imidazole, hydrogen peroxide and curcumin concentration were optimized. Moreover, application of curcumin makes it possible to design a system for selective tumor destruction. In the reaction of peroxyoxalate, it acts as an oxalate activator with intracellular hydrogen peroxide and experiences excitation as a result of the reaction. In addition, curcumin also acts as a photosensitizer (PS) causing cell damage. In the optimum conditions, the measurable concentration range of 0.86-220 μM of hydrogen peroxide were evaluated from the linear calibration curve with satisfactory RSD% and corresponding detection limits of 650 nM. Therefore, it has the sensitivity needed to detect physiological concentrations of hydrogen peroxide. Moreover, cellular uptake experiments showed that the liposomes enhance extravasation into permeable membranes and significantly increased the bioavailability of curcumin., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Gold nanoparticles (AuNPs) are considered suitable systems for drug delivery and diagnostics with several applications in biomedicine. Size, shape and surface functionalization of these nanoparticles are important parameters influencing their behavior in a biological environment. This study describes the preparation and the characterization of lysophosphocholine coated AuNPs by means of Small Angle Neutron Scattering (SANS), Electron Paramagnetic Resonance (EPR) and Fluorescence Spectroscopy. In particular the structure of the functionalized AuNP suspension, as well as the physical properties, of the nanoparticle organic coating are discussed. The experimental results indicated that functionalized lysophosphocholine-AuNPs form aggregates, which are composed by nanoparticles with core-shell structure. Nevertheless, the nanoparticle suspension resulted to be stable, without significant structural rearrangements even when the temperature was increased to 50 °C. At the same time, experimental evidences also suggested that the 18LPC layer around AuNPs presented a reduced chain packing compared to pure 18LPC aggregates., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The authors describe a novel water-soluble, stable, biocompatible, and highly fluorescent probe consisting of iron quantum clusters incorporated into human adult hemoglobin (Hb-FeQCs). The Hb-FeQCs were characterized by various spectroscopic techniques. The probe displays strong absorption and yellow fluorescence with a peak centered at 567 nm (photo-excited at 460 nm). The Hb-FeQCs show excellent photostability over a wide range of pH values (5-12), even in the presence of high electrolyte concentrations. A colorimetric and a fluorometric method were worked out for the quantitation Zn(II) and cysteine in aqueous solution. Zinc ions induce a visible color change from brown to yellow. The sensitivity of Hb-FeQCs towards other metal ions was negligible, with the exception of Co 2+ and Cu 2+ , which caused a modest interference. The Hb-FeQCs were exploited in a sensitive and selective turn-on fluorescence assay for Zn 2+ . It is also found that cysteine quenches the fluorescence of the Hb-FeQCs/Zn(II) complex. Under the optimized conditions, the probe has a linear response in the 0.04 to 2.2 μM Zn(II) concentration range, with a 48 nM detection limit. Response to cysteine is linear in the 1-60 μM concentration range, with a 0.25 μM limit of detection. This fluorescent probe undergoes fluorescent emission intensity enhancement upon binding to zinc ions in living normal human fibroblast cells under visible lamp. The cellular imaging capability and very low cytotoxicity of this soluble iron quantum clusters can be potentially extended as an exciting sub-nanoplatform with promising biomaterial applications. Graphical abstract Schematic of yellow-emitting iron quantum clusters in hemoglobin matrix (Hb-FeQCs) were characterized and successfully applied for sensing zinc(II) and cysteine. The act as an on-off fluorescent probe and can be applied to image zinc ions in human fibroblast cells under visible light.

The interaction of lipid environments with the type I' β-turn peptide structure called CSF114 and its N-glucosylated form CSF114(Glc), previously developed as a synthetic antigenic probe recognizing specific autoantibodies in a subpopulation of multiple sclerosis patients' serum, was investigated by fluorescence spectroscopy and electrochemical experiments using large unilamellar vesicles, mercury supported lipid self-assembled monolayers (SAMs) and tethered bilayer lipid membranes (tBLMs). The synthetic antigenic probe N-glucosylated peptide CSF114(Glc) and its unglucosylated form interact with the polar heads of lipid SAMs of dioleoylphosphatidylcholine at nonzero transmembrane potentials, probably establishing a dual electrostatic interaction of the trimethylammonium  and phosphate groups of the phosphatidylcholine polar head with the Glu⁵ and His⁸ residues on the opposite ends of the CSF114(Glc) β-turn encompassing residues 6-9. His⁸ protonation at pH 7 eliminates this dual interaction. CSF114(Glc) is adsorbed on top of SAMs of mixtures of dioleoylphosphatidylcholine with sphingomyelin, an important component of myelin, whose proteins are hypothesized to undergo an aberrant N-glucosylation triggering the autoimmune response. Incorporation of the type I' β-turn peptide structure CSF114 into lipid SAMs by potential scans of electrochemical impedance spectroscopy induces defects causing a slight permeabilization toward cadmium ions. The N-glucopeptide CSF114(Glc) does not affect  tBLMs to a detectable extent.

The enhancing effect of histidine and tryptophan on chemiluminescence (CL) of CdSe quantum dots (QDs)-H2O2 system was studied. This reaction is based on the catalytic effect of amino acids, causing a significant increase in the light emission, as a result of the reaction of quantum dots (QDs) with hydrogen peroxide. In the optimum conditions, this method was satisfactorily described by linear calibration curve in the range of 0.66-35.5 μM and 0.83-35.1 μM for histidine and tryptophan, respectively. The effect of various parameters such as concentration of CdSe QDs, concentration of H2O2 and concentration of imidazole on the intensity of CL system were studied. The main experimental advantage of the proposed method is it's selective to two amino acids compared with other amino acids., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The intensity of emitted light from CdSe quantum dots (QDs)-H2O2 is described as a novel chemiluminescence (CL) reaction for determination of dysprosium. This reaction is based on the catalytic effect of Dy(3+) ions, causing a significant increase in the light emission, as a result of the reaction of quantum dots (QDs) with hydrogen peroxide. In the optimum conditions, this method was satisfactorily described by linear calibration curve in the range of 8.3×10(-7)-5.0×10(-6)M, the detection limit of 6.0×10(-8)M, and the relative standard deviation for five determinations of 2.5×10(-6)M Dy(3+) 3.2%. The main experimental advantage of the proposed method is its selective to Dy(3+) ions compared with common coexisting cations, therefore, it was successfully applied for the determination of dysprosium ions in water samples., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A new fluorogenic method for selective and sensitive determination of beryllium using 2,6-diphenyl-4-benzo-9-crown-3-pyrane (DBCP) was developed. The proposed fluorescent probe undergoes fluorescent emission intensity enhancement upon binding to beryllium ions in MeOH/H(2)O (70:30, v/v) solution. The fluorescence enhancement of DBCP is attributed to a 1:1 complex formation between DBCP and Be(2+) ion, which has been utilized as the basis for selective detection of Be(2+) ion. With the optimum condition described, the fluorescence enhancement at 531 nm was linear to the concentration of beryllium in the range of 1.6×10(-8)-1.6×10(-7) M and a detection limit of 1.5×10(-9) M. The fluorescent probe exhibits high selectivity for Be(2+) ion over the other common mono, di- and trivalent cations., (Copyright © 2011 Elsevier B.V. All rights reserved.)

N,N'-phenylenebis(salicylideaminato) (L) has been used to detect trace amounts of zinc ion in acetonitrile-water solution by fluorescence spectroscopy. The fluorescent probe undergoes fluorescent emission intensity enhancement upon binding to zinc ions in MeCN/H(2)O (1:1, v/v) solution. The fluorescence enhancement of L is attributed to the 1:1 complex formation between L and Zn(II), which has been utilized as the basis for selective detection of Zn(II). The linear response range for Zn(II) covers a concentration range of 1.6x10(-7) to 1.0x10(-5)mol/L, and the detection limit is 1.5x10(-7)mol/L. The fluorescent probe exhibits high selectivity over other common metal ions, and the proposed fluorescent sensor was applied to determine zinc in water samples and waste water., (Copyright 2009 Elsevier B.V. All rights reserved.)