132 results on '"Ratera I"'
Search Results
2. Friction-anisotropy dependence in organic self-assembled monolayers
- Author
-
Chen, J., Ratera, I., Murphy, A., Ogletree, D.F., Fréchet, J.M.J., and Salmeron, M.
- Published
- 2006
- Full Text
- View/download PDF
3. Metal ion bombardment of onion skin cell wall
- Author
-
Sangyuenyongpipat, S., Vilaithong, T., Yu, L.D., Verdaguer, A., Ratera, I., Ogletree, D.F., Monteiro, O.R., and Brown, I.G.
- Published
- 2005
- Full Text
- View/download PDF
4. Nonlinear optical properties of open-shell polychlorotriphenylmethyl radicals
- Author
-
Ratera, I, Ruiz-Molina, D, Sporer, C, Marcen, S, Montant, S, Létard, J.-F, Freysz, E, Rovira, C, and Veciana, J
- Published
- 2003
- Full Text
- View/download PDF
5. EPR study of the trans and cis isomers of a ferrocenyl Schiff-based polychlorotriphenylmethyl radical
- Author
-
Ratera, I, Ruiz-Molina, D, Vidal-Gancedo, J, Rovira, C, and Veciana, J
- Published
- 2001
- Full Text
- View/download PDF
6. Ferrocene as a ferromagnetic coupler. Synthesis and characterization of a ferrocene bridged polychlorotriphenylmethyl diradical
- Author
-
Elsner, O, Ruiz-Molina, D, Ratera, I, Vidal-Gancedo, J, Rovira, C, and Veciana, J
- Published
- 2001
- Full Text
- View/download PDF
7. Functional protein-based nanomaterial produced in microorganisms recognized as safe: A new platform for biotechnology
- Author
-
Cano Garrido, O, Sánchez Chardi, A, Parés, S, Giró, I, Tatkiewicz, W, Ferrer Miralles, N, Ratera, I, Natalello, A, Cubarsi, R, Veciana, J, Bach, À, Villaverde, A, Arís, A, Garcia Fruitós, E, NATALELLO, ANTONINO, Garcia Fruitós, E., Cano Garrido, O, Sánchez Chardi, A, Parés, S, Giró, I, Tatkiewicz, W, Ferrer Miralles, N, Ratera, I, Natalello, A, Cubarsi, R, Veciana, J, Bach, À, Villaverde, A, Arís, A, Garcia Fruitós, E, NATALELLO, ANTONINO, and Garcia Fruitós, E.
- Abstract
Inclusion bodies (IBs) are protein-based nanoparticles formed in Escherichia coli through stereospecific aggregation processes during the overexpression of recombinant proteins. In the last years, it has been shown that IBs can be used as nanostructured biomaterials to stimulate mammalian cell attachment, proliferation, and differentiation. In addition, these nanoparticles have also been explored as natural delivery systems for protein replacement therapies. Although the production of these protein-based nanomaterials in E. coli is economically viable, important safety concerns related to the presence of endotoxins in the products derived from this microorganism need to be addressed. Lactic acid bacteria (LAB) are a group of food-grade microorganisms that have been classified as safe by biologically regulatory agencies. In this context, we have demonstrated herein, for the first time, the production of fully functional, IB-like protein nanoparticles in LAB. These nanoparticles have been fully characterized using a wide range of techniques, including field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, zymography, cytometry, confocal microscopy, and wettability and cell coverage measurements. Our results allow us to conclude that these materials share the main physico-chemical characteristics with IBs from E. coli and moreover are devoid of any harmful endotoxin contaminant. These findings reveal a new platform for the production of protein-based safe products with high pharmaceutical interest. Statement of Significance The development of both natural and synthetic biomaterials for biomedical applications is a field in constant development. In this context, E. coli is a bacteria that has been widely studied for its ability to naturally produce functional biomaterials with broad biomedical uses. Despite being effective, products derived from this spe
- Published
- 2016
8. Functionalization of 3D scaffolds with protein-releasing biomaterials for intracellular delivery
- Author
-
Seras-Franzoso J, Steurer C, Roldán M, Vendrell M, Vidaurre-Agut C, Tarruella A, Saldaña L, Vilaboa N, Parera M, Elizondo E, Ratera I, Ventosa N, Veciana J, Campillo-Fernández AJ, García-Fruitós E, Vázquez E, and Villaverde A
- Subjects
3D scaffolds, Bioscaffold, Bottom-up delivery, Nanoparticles, Polylactic acid (PLA), Tissue engineering - Abstract
Appropriate combinations of mechanical and biological stimuli are required to promote proper colonization of substrate materials in regenerative medicine. In this context, 3D scaffolds formed by compatible and biodegradable materials are under continuous development in an attempt to mimic the extracellular environment of mammalian cells. We have here explored how novel 3D porous scaffolds constructed by polylactic acid, polycaprolactone or chitosan can be decorated with bacterial inclusion bodies, submicron protein particles formed by releasable functional proteins. A simple dipping-based decoration method tested here specifically favors the penetration of the functional particles deeper than 300µm from the materials' surface. The functionalized surfaces support the intracellular delivery of biologically active proteins to up to more than 80% of the colonizing cells, a process that is slightly influenced by the chemical nature of the scaffold. The combination of 3D soft scaffolds and protein-based sustained release systems (Bioscaffolds) offers promise in the fabrication of bio-inspired hybrid matrices for multifactorial control of cell proliferation in tissue engineering under complex architectonic setting-ups.
- Published
- 2013
9. Inverted Marcus Region of Intramolecular Electron Transfer in Ferrocene-Based Organic Radicals
- Author
-
Ratera, I., Sporer, C., Ruiz-Molina, D., Ventosa, N., Baggerman, J., Brouwer, A.M., Rovira, C., Veciana, J., and Spectroscopy and Photonic Materials (HIMS, FNWI)
- Published
- 2007
10. Organic radicals for the enhancement of oxygen reduction reaction in Li–O2 batteries
- Author
-
Tesio, A. Y., primary, Blasi, D., additional, Olivares-Marín, M., additional, Ratera, I., additional, Tonti, D., additional, and Veciana, J., additional
- Published
- 2015
- Full Text
- View/download PDF
11. Ultra-flat coplanar electrodes for controlled electrical contact of molecular films
- Author
-
Martin, F., Hendriksen, B.L.M., Katan, A.J., Ratera, I., Qi, Y., Harteneck, B., Liddle, J.A., Salmer, M., Martin, F., Hendriksen, B.L.M., Katan, A.J., Ratera, I., Qi, Y., Harteneck, B., Liddle, J.A., and Salmer, M.
- Abstract
Contains fulltext : 92524.pdf (publisher's version ) (Open Access)
- Published
- 2011
12. Influence of Molecular Ordering on Electrical and Friction Properties of omega-(trans-4-Stilbene)Alkylthiol Self-Assembled Monolayers on Au (111)
- Author
-
Qi, Y.B., Liu, X.S., Hendriksen, B.L.M., Navarro, V., Park, J.Y., Ratera, I., Klopp, J.M., Edder, C., Himpsel, F.J., Frechet, J.M.J., Haller, E.E., Salmeron, M., Qi, Y.B., Liu, X.S., Hendriksen, B.L.M., Navarro, V., Park, J.Y., Ratera, I., Klopp, J.M., Edder, C., Himpsel, F.J., Frechet, J.M.J., Haller, E.E., and Salmeron, M.
- Abstract
Item does not contain fulltext
- Published
- 2010
13. Multidimensional Supramolecular Organizations Based on Polychlorotriphenyl‐Methyl Radicals
- Author
-
Mugnaini, V., primary, Mas‐Torrent, M., additional, Ratera, I., additional, Rovira, C., additional, and Veciana, J., additional
- Published
- 2011
- Full Text
- View/download PDF
14. Bacterially produced inclusion bodies as biocompatible materials for substrate-dependent mammalian cell proliferation
- Author
-
Seras, J., primary, Díez-Gil, C., additional, Vazquez, E., additional, Krabbenborg, S., additional, Rodríguez-Carmona, E., additional, Corchero, J.L., additional, Ferraz, R.M., additional, Cano-Sarabia, M., additional, Ratera, I., additional, and Ventosa, N., additional
- Published
- 2010
- Full Text
- View/download PDF
15. Bacterial inclusion bodies as novel functional and biocompatible nanomaterials
- Author
-
García-Fruitós, E., primary, Rodríguez-Carmona, E., additional, Díez-Gil, C., additional, Ferraz, R.M., additional, Vázquez, E., additional, Corchero, J.L., additional, Cano-Sarabia, M., additional, Ratera, I., additional, Ventosa, N., additional, Veciana, J., additional, and Villaverde, A., additional
- Published
- 2009
- Full Text
- View/download PDF
16. Organic radicals on surfaces: towards molecular spintronics
- Author
-
Mas-Torrent, M., primary, Crivillers, N., additional, Mugnaini, V., additional, Ratera, I., additional, Rovira, C., additional, and Veciana, J., additional
- Published
- 2009
- Full Text
- View/download PDF
17. In situphotoelectron spectroscopy study of water adsorption on model biomaterial surfaces
- Author
-
Ketteler, G, primary, Ashby, P, additional, Mun, B S, additional, Ratera, I, additional, Bluhm, H, additional, Kasemo, B, additional, and Salmeron, M, additional
- Published
- 2008
- Full Text
- View/download PDF
18. Cellulose-Based Optical Sensor for the Selective and Quantitative Detection of Mercury Ions in Aqueous Media
- Author
-
Diez-Gil, C., primary, Caballero, A., additional, Martinez, R., additional, Ratera, I., additional, Tarraga, A., additional, Molina, P., additional, and Veciana, J., additional
- Published
- 2007
- Full Text
- View/download PDF
19. Organic radicals for the enhancement of oxygen reduction reaction in Li–O2 batteries.
- Author
-
Tesio, A. Y., Blasi, D., Olivares-Marín, M., Ratera, I., Tonti, D., and Veciana, J.
- Subjects
RADICALS (Chemistry) ,OXYGEN reduction ,LITHIUM cells ,ELECTROLYTES ,OXIDATION-reduction reaction - Abstract
We examine for the first time the ability of inert carbon free-radicals as soluble redox mediators to catalyze and enhance the oxygen reduction reaction in a (TEGDME)-based electrolyte. We demonstrate that the tris(2,4,6-trichlorophenyl)methyl (TTM) radical is capable of chemically favoring the oxygen reduction reaction improving significantly the Li–O
2 battery performance. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
20. Atomic force microscopy nanotribology study of oligothiophene self-assembled films
- Author
-
Ratera, I, primary, Chen, J, additional, Murphy, A, additional, Ogletree, D F, additional, Fréchet, J M J, additional, and Salmeron, M, additional
- Published
- 2005
- Full Text
- View/download PDF
21. Nonlinear optical properties of polychlorotriphenylmethyl radicals: towards the design of `super-octupolar' molecules
- Author
-
Ratera, I, primary, Marcen, S, additional, Montant, S, additional, Ruiz–Molina, D, additional, Rovira, C, additional, Veciana, J, additional, Létard, J.-F, additional, and Freysz, E, additional
- Published
- 2002
- Full Text
- View/download PDF
22. Formation of a biradical species from a monoradical with a photo- and thermo isomerizable imine group
- Author
-
Ruiz-Molina, D., primary, Ratera, I., additional, Vidal-Gancedo, J., additional, Daro, N., additional, Létard, J.-F., additional, Rovira, C., additional, and Veciana, J., additional
- Published
- 2001
- Full Text
- View/download PDF
23. Nonlinear optical properties of a new stable ferrocenyl Schiff-base polychlorotriphenylmethyl radical
- Author
-
Ratera, I., primary, Ruiz-Molina, D., additional, Sánchez, C., additional, Alcalá, R., additional, Rovira, C., additional, and Veciana, J., additional
- Published
- 2001
- Full Text
- View/download PDF
24. In situ photoelectron spectroscopy study of water adsorption on model biomaterial surfaces.
- Author
-
Ketteler, G, Ashby, P, Mun, B S, Ratera, I, Bluhm, H, Kasemo, B, and Salmeron, M
- Published
- 2008
- Full Text
- View/download PDF
25. Atomic Force Microscopy Study of β-Substituted-T7 Oligothiophene Films on Mica: Mechanical Properties and Humidity-Dependent Phases
- Author
-
Chen, J., Ratera, I., Ogletree, D. F., Salmeron, M., Murphy, A. R., and Frechet, J. M. J.
- Abstract
The structural and mechanical properties of Langmuir−Blodgett monolayer and multilayer films of 3 ,4 -didecyl-5,2;5,2 ;5 ,2 ;5 ,2 ;5 ,2 ;5 ,2 -heptathiophene-4 -acetic acid on mica have been studied by atomic force microscopy (AFM) as a function of humidity, temperature, and applied force. The molecules orient with the carboxylic acid group pointing toward the mica surface and expose the alkyl side chains to the air interface. As the load applied by the AFM tip increases, the film is compressed easily from an initial height of 2 to 1.2 nm. After compression the films can support much higher loads without loss of height. The state of aggregation of the molecules was found to be sensitive to the environmental humidity, which induced reversible changes. Annealing the samples with monolayer or multilayer films resulted in irreversible changes when the temperature exceeded approximately 100 °C.
- Published
- 2005
26. Ferrocene triphenylmethyl radical donor-acceptor compounds. Towards the development of multifunctional molecular switches
- Author
-
Sporer, C., Ratera, I., Wurst, K., Vidal-Gancedo, J., Daniel Ruiz-Molina, Rovira, C., and Veciana, J.
27. Functional protein-based nanomaterial produced in microorganisms recognized as safe: A new platform for biotechnology
- Author
-
Witold I. Tatkiewicz, Alex Bach, Antonino Natalello, Anna Arís, Imma Ratera, Alejandro Sánchez-Chardi, Irene Giró, Sílvia Parés, Elena García-Fruitós, Olivia Cano-Garrido, Antonio Villaverde, Neus Ferrer-Miralles, Rafael Cubarsi, Jaume Veciana, Universitat Politècnica de Catalunya. Departament de Matemàtiques, Universitat Politècnica de Catalunya. gAGE - Grup d'Astronomia i Geomàtica, Cano Garrido, O, Sánchez Chardi, A, Parés, S, Giró, I, Tatkiewicz, W, Ferrer Miralles, N, Ratera, I, Natalello, A, Cubarsi, R, Veciana, J, Bach, À, Villaverde, A, Arís, A, Garcia Fruitós, E, Ministerio de Economía y Competitividad (España), Generalitat de Catalunya, European Commission, and Dirección General de Investigación Científica y Técnica, DGICT (España)
- Subjects
0301 basic medicine ,Time Factors ,Nanoparticle ,Matemàtiques i estadística::Matemàtica discreta::Combinatòria [Àrees temàtiques de la UPC] ,Numerical analysis--Simulation methods ,medicine.disease_cause ,Biochemistry ,Inclusion bodies ,Nanomaterials ,law.invention ,law ,Functional nanomaterials ,Spectroscopy, Fourier Transform Infrared ,Lactic acid bacteria ,Matemàtiques i estadística::Probabilitat [Àrees temàtiques de la UPC] ,biology ,General Medicine ,Functional nanomaterial ,Recombinant Proteins ,3. Good health ,Endotoxin-free ,Combinatorial probabilities ,Hydrophobic and Hydrophilic Interactions ,Biotechnology ,Materials science ,Static Electricity ,Biomedical Engineering ,FIS/07 - FISICA APPLICATA (A BENI CULTURALI, AMBIENTALI, BIOLOGIA E MEDICINA) ,Context (language use) ,92 Biology and other natural sciences::92D Genetics and population dynamics [Classificació AMS] ,Biomaterials ,03 medical and health sciences ,60 Probability theory and stochastic processes::60C05 Combinatorial probability [Classificació AMS] ,Dynamic light scattering ,Confocal microscopy ,GRAS ,medicine ,Escherichia coli ,Genetics ,Humans ,65 Numerical analysis::65C Probabilistic methods, simulation and stochastic differential equations [Classificació AMS] ,Particle Size ,Molecular Biology ,Anàlisi numèrica ,Matemàtiques i estadística::Estadística aplicada::Estadística biosanitària [Àrees temàtiques de la UPC] ,business.industry ,biology.organism_classification ,Biomaterial ,Nanostructures ,Lactobacillus ,030104 developmental biology ,Nanoparticles ,Probabilitats ,business ,Bacteria ,Genètica ,HeLa Cells - Abstract
Cano Garrido, Olivia et al., Inclusion bodies (IBs) are protein-based nanoparticles formed in Escherichia coli through stereospecific aggregation processes during the overexpression of recombinant proteins. In the last years, it has been shown that IBs can be used as nanostructured biomaterials to stimulate mammalian cell attachment, proliferation, and differentiation. In addition, these nanoparticles have also been explored as natural delivery systems for protein replacement therapies. Although the production of these protein-based nanomaterials in E. coli is economically viable, important safety concerns related to the presence of endotoxins in the products derived from this microorganism need to be addressed. Lactic acid bacteria (LAB) are a group of food-grade microorganisms that have been classified as safe by biologically regulatory agencies. In this context, we have demonstrated herein, for the first time, the production of fully functional, IB-like protein nanoparticles in LAB. These nanoparticles have been fully characterized using a wide range of techniques, including field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, zymography, cytometry, confocal microscopy, and wettability and cell coverage measurements. Our results allow us to conclude that these materials share the main physico-chemical characteristics with IBs from E. coli and moreover are devoid of any harmful endotoxin contaminant. These findings reveal a new platform for the production of protein-based safe products with high pharmaceutical interest., This work was supported by grants from INIA, MINECO, Spain to AA and EGF (RTA2012-00028-C02-02), from DGI to JV (BeWell CTQ2013-40480-R), from MINECO to EGF and IR (MAT2013-50036-EXP) and to ICMAB (Severo Ochoa Programme for Centres of Excellence in R&D – SEV – 2015-0496), from Agència de Gestió d’Ajuts Universitaris i de Recerca to AV and JV (2014SGR-132 and 2014-SGR-17, respectively) and from EU to JV, AV and IR (H2020-INFRAIA-2014-2015; NFFA-654360). Besides, the authors acknowledge the financial support granted to AV and JV from the Centro de Investigación Biomédica en Red (CIBER) de Bioingeniería, Biomateriales y Nanomedicina financed by the Instituto de Salud Carlos III with assistance from the European Regional Development. OCG and WIT received a PhD fellowship from MECD (FPU) and CSIC (JAE-pre), respectively, and EGF a post-doctoral fellowship from INIA (DOC-INIA). AV has been distinguished with an ICREA ACADEMIA Award. The authors also acknowledge Micalis Institute, INRA, France that kindly provide us the strain clpP− htrA−-NZ9000 (patent n° EP1141337B1/US6994997B1). We are also indebted to “Servei de Microscopia” (UAB) and ICTS “NANBIOSIS”, more specifically to the Protein Production Platform of CIBER in Bioengineering, Biomaterials & Nanomedicine (CIBER-BBN)/IBB, at the UAB SepBioES scientific-technical service (http://www.nanbiosis.es/unit/u1-protein-production-platform-ppp/). No other potential conflicts of interest were identified.
- Published
- 2016
28. Activating Thermoplastic Polyurethane Surfaces with Poly(ethylene glycol)-Based Recombinant Human α-Defensin 5 Monolayers for Antibiofilm Activity.
- Author
-
Rodríguez Rodríguez X, López-Cano A, Mayolo-Deloisa K, Pich OQ, Bierge P, Ventosa N, García-de-la-Maria C, Miró JM, Gasch O, Veciana J, Guasch J, Arís A, Garcia-Fruitós E, and Ratera I
- Abstract
Addressing multidrug-resistant microbial infections linked to implantable biomedical devices is an urgent need. In recent years, there has been an active exploration of different surface coatings to prevent and combat drug-resistant microbes. In this research, we present a facile chemical modification of thermoplastic polyurethane (TPU) surfaces with poly(ethylene glycol)-based recombinant human α-defensin 5 (HD5) protein with antimicrobial activity. TPU is one of the most relevant materials used for medical devices with good mechanical properties but also good chemical resistance, which makes it difficult to modify. The chemical modification of TPU surfaces is achieved via a three-step procedure based on (i) TPU activation using hexamethylene diisocyanate (HDI); (ii) interfacial reaction with poly(ethylene glycol) (PEG) derivatives; and finally, (iii) a facile click reaction between the PEG-maleimide terminated assembled monolayers on the TPU and the cysteine (-thiol) termination of the recently designed recombinant human α-defensin 5 (HD5) protein. The obtained PEG based HD5 assembled monolayers on TPU were characterized using a surface science multitechnique approach including scanning electron microscopy, atomic force microscopy, contact angle, and X-ray photoelectron spectroscopy. The modified TPU surfaces with the HD5 protein derivative exhibit broad-spectrum antibacterial properties reducing biofilm formation against Pseudomonas aeruginosa (Gram-negative), methicillin-resistant Staphylococcus aureus (MRSA) (Gram-positive) and methicillin-resistant Staphylococcus epidermidis (MRSE) (Gram-positive). These findings underscore the substantial potential of protein-modified TPU surfaces for applications in combating bacterial infections associated with implantable materials and devices.
- Published
- 2025
- Full Text
- View/download PDF
29. 3D Printing as a Strategy to Scale-Up Biohybrid Hydrogels for T Cell Manufacture.
- Author
-
Pérez Del Río E, Rey-Vinolas S, Santos F, Castellote-Borrell M, Merlina F, Veciana J, Ratera I, Mateos-Timoneda MA, Engel E, and Guasch J
- Subjects
- Humans, Cell Proliferation drug effects, Heparin chemistry, Cells, Cultured, Hydrogels chemistry, Printing, Three-Dimensional, T-Lymphocytes cytology, T-Lymphocytes immunology, Polyethylene Glycols chemistry
- Abstract
The emergence of cellular immunotherapy treatments is introducing more efficient strategies to combat cancer as well as autoimmune and infectious diseases. However, the cellular manufacturing procedures associated with these therapies remain costly and time-consuming, thus limiting their applicability. Recently, lymph-node-inspired PEG-heparin hydrogels have been demonstrated to improve primary human T cell culture at the laboratory scale. To go one step further in their clinical applicability, we assessed their scalability, which was successfully achieved by 3D printing. Thus, we were able to improve primary human T cell infiltration in the biohybrid PEG-heparin hydrogels, as well as increase nutrient, waste, and gas transport, resulting in higher primary human T cell proliferation rates while maintaining the phenotype. Thus, we moved one step further toward meeting the requirements needed to improve the manufacture of the cellular products used in cellular immunotherapies.
- Published
- 2024
- Full Text
- View/download PDF
30. Nanothermometer Based on Polychlorinated Trityl Radicals Showing Two-Photon Excitation and Emission in the Biological Transparency Window: Temperature Monitoring of Biological Tissues.
- Author
-
Gonzalez-Pato N, Blasi D, Nikolaidou DM, Bertocchi F, Cerdá J, Terenziani F, Ventosa N, Aragó J, Lapini A, Veciana J, and Ratera I
- Subjects
- Humans, Female, Pregnancy, Animals, Swine, Temperature, Thermometers, Postnatal Care, Luminescence, Nanoparticles chemistry
- Abstract
Nanothermometers are emerging probes as biomedical diagnostic tools. Especially appealing are nanoprobes using NIR light in the range of biological transparency window (BTW) since they have the advantages of a deeper penetration into biological tissues, better contrast, reduced phototoxicity and photobleaching. This article reports the preparation and characterization of organic nanoparticles (ONPs) doped with two polychlorinated trityl radicals (TTM and PTM), as well as studies of their electronic and optical properties. Such ONPs having inside isolated radical molecules and dimeric excimers, can be two-photon excited showing optimal properties for temperature sensing. Remarkably, in TTM-based ONPs the emission intensity of the isolated radical species is unaltered increasing temperature, while the excimer emission intensity decreases strongly being thereby able to monitor temperature changes with an excellent thermal absolute sensitivity of 0.6-3.7% K
-1 in the temperature range of 278-328 K. The temperature dependence of the excimeric bands of ONPs are theoretically simulated by using electronic structure calculations and a vibronic Hamiltonian model. Finally, TTM-doped ONPs as ratiometric NIR-nanothermometers are tested with two-photon excitationwith enucleated pig eye sclera, as a real tissue model, obtaining a similar temperature sensitivity as in aqueous suspensions, demonstrating their potential as NIR nanothermometers for bio applications., (© 2023 The Authors. Small Methods published by Wiley-VCH GmbH.)- Published
- 2024
- Full Text
- View/download PDF
31. Three-dimensional cell culture of chimeric antigen receptor T cells originated from peripheral blood mononuclear cells towards cellular therapies.
- Author
-
Pérez Del Río E, Román Alonso M, Rius I, Santos F, Castellote-Borrell M, Veciana J, Ratera I, Arribas J, and Guasch J
- Subjects
- Polystyrenes, Cell Culture Techniques, Three Dimensional, T-Lymphocytes, Leukocytes, Mononuclear, Receptors, Chimeric Antigen genetics
- Abstract
Background Aims: With the objective of improving the ex vivo production of therapeutic chimeric antigen receptor (CAR) T cells, we explored the addition of three-dimensional (3D) polystyrene scaffolds to standard suspension cell cultures., Methods: We aimed to mimic the structural support given by the lymph nodes during in vivo lymphocyte expansion., Results: We observed an increase in cell proliferation compared with standard suspension systems as well as an enhanced cytotoxicity toward cancer cells. Moreover, we directly obtained the CAR T cells from peripheral blood mononuclear cells, thus minimizing the ex vivo manipulation of the therapeutic cells and opening the way to synergies among different cell populations., Conclusions: We propose the use of commercially available 3D polystyrene systems to improve the current immune cell cultures and resulting cell products for emerging cellular (immuno)therapies., Competing Interests: Declaration of Competing Interest The authors have no commercial, proprietary or financial interest in the products or companies described in this article., (Copyright © 2023 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
32. Ratiometric Nanothermometer Based on a Radical Excimer for In Vivo Sensing.
- Author
-
Blasi D, Gonzalez-Pato N, Rodriguez Rodriguez X, Diez-Zabala I, Srinivasan SY, Camarero N, Esquivias O, Roldán M, Guasch J, Laromaine A, Gorostiza P, Veciana J, and Ratera I
- Subjects
- Animals, Caenorhabditis elegans, Temperature, Thermometry, Nanoparticles
- Abstract
Ratiometric fluorescent nanothermometers with near-infrared emission play an important role in in vivo sensing since they can be used as intracellular thermal sensing probes with high spatial resolution and high sensitivity, to investigate cellular functions of interest in diagnosis and therapy, where current approaches are not effective. Herein, the temperature-dependent fluorescence of organic nanoparticles is designed, synthesized, and studied based on the dual emission, generated by monomer and excimer species, of the tris(2,4,6-trichlorophenyl)methyl radical (TTM) doping organic nanoparticles (TTMd-ONPs), made of optically neutral tris(2,4,6-trichlorophenyl)methane (TTM-αH), acting as a matrix. The excimer emission intensity of TTMd-ONPs decreases with increasing temperatures whereas the monomer emission is almost independent and can be used as an internal reference. TTMd-ONPs show a great temperature sensitivity (3.4% K
-1 at 328 K) and a wide temperature response at ambient conditions with excellent reversibility and high colloidal stability. In addition, TTMd-ONPs are not cytotoxic and their ratiometric outputs are unaffected by changes in the environment. Individual TTMd-ONPs are able to sense temperature changes at the nano-microscale. In vivo thermometry experiments in Caenorhabditis elegans (C. elegans) worms show that TTMd-ONPs can locally monitor internal body temperature changes with spatio-temporal resolution and high sensitivity, offering multiple applications in the biological nanothermometry field., (© 2023 The Authors. Small published by Wiley-VCH GmbH.)- Published
- 2023
- Full Text
- View/download PDF
33. Strategies for surface coatings of implantable cardiac medical devices.
- Author
-
Coronel-Meneses D, Sánchez-Trasviña C, Ratera I, and Mayolo-Deloisa K
- Abstract
Cardiac medical devices (CMDs) are required when the patient's cardiac capacity or activity is compromised. To guarantee its correct functionality, the building materials in the development of CMDs must focus on several fundamental properties such as strength, stiffness, rigidity, corrosion resistance, etc. The challenge is more significant because CMDs are generally built with at least one metallic and one polymeric part. However, not only the properties of the materials need to be taken into consideration. The biocompatibility of the materials represents one of the major causes of the success of CMDs in the short and long term. Otherwise, the material will lead to several problems of hemocompatibility (e.g., protein adsorption, platelet aggregation, thrombus formation, bacterial infection, and finally, the rejection of the CMDs). To enhance the hemocompatibility of selected materials, surface modification represents a suitable solution. The surface modification involves the attachment of chemical compounds or bioactive compounds to the surface of the material. These coatings interact with the blood and avoid hemocompatibility and infection issues. This work reviews two main topics: 1) the materials employed in developing CMDs and their key characteristics, and 2) the surface modifications reported in the literature, clinical trials, and those that have reached the market. With the aim of providing to the research community, considerations regarding the choice of materials for CMDs, together with the advantages and disadvantages of the surface modifications and the limitations of the studies performed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Coronel-Meneses, Sánchez-Trasviña, Ratera and Mayolo-Deloisa.)
- Published
- 2023
- Full Text
- View/download PDF
34. A Novel Generation of Tailored Antimicrobial Drugs Based on Recombinant Multidomain Proteins.
- Author
-
López-Cano A, Ferrer-Miralles N, Sánchez J, Carratalá JV, Rodriguez XR, Ratera I, Guasch J, Pich OQ, Bierge P, Garcia-de-la-Maria C, Miro JM, Garcia-Fruitós E, and Arís A
- Abstract
Antibiotic resistance has exponentially increased during the last years. It is necessary to develop new antimicrobial drugs to prevent and treat infectious diseases caused by multidrug- or extensively-drug resistant (MDR/XDR)-bacteria. Host Defense Peptides (HDPs) have a versatile role, acting as antimicrobial peptides and regulators of several innate immunity functions. The results shown by previous studies using synthetic HDPs are only the tip of the iceberg, since the synergistic potential of HDPs and their production as recombinant proteins are fields practically unexplored. The present study aims to move a step forward through the development of a new generation of tailored antimicrobials, using a rational design of recombinant multidomain proteins based on HDPs. This strategy is based on a two-phase process, starting with the construction of the first generation molecules using single HDPs and further selecting those HDPs with higher bactericidal efficiencies to be combined in the second generation of broad-spectrum antimicrobials. As a proof of concept, we have designed three new antimicrobials, named D5L37βD3, D5L37D5L37 and D5LAL37βD3. After an in-depth exploration, we found D5L37D5L37 to be the most promising one, since it was equally effective against four relevant pathogens in healthcare-associated infections, such as methicillin-susceptible (MSSA) and methicillin-resistant (MRSA) Staphylococcus aureus , methicillin-resistant Staphylococcus epidermidis (MRSE) and MDR Pseudomonas aeruginosa , being MRSA, MRSE and P. aeruginosa MDR strains. The low MIC values and versatile activity against planktonic and biofilm forms reinforce the use of this platform to isolate and produce unlimited HDP combinations as new antimicrobial drugs by effective means.
- Published
- 2023
- Full Text
- View/download PDF
35. Stable nanovesicles formed by intrinsically planar bilayers.
- Author
-
Köber M, Illa-Tuset S, Ferrer-Tasies L, Moreno-Calvo E, Tatkiewicz WI, Grimaldi N, Piña D, Pérez AP, Lloveras V, Vidal-Gancedo J, Bulone D, Ratera I, Pedersen JS, Danino D, Veciana J, Faraudo J, and Ventosa N
- Subjects
- Cetrimonium, Cryoelectron Microscopy, Cholesterol chemistry, Lipid Bilayers chemistry, Cetrimonium Compounds chemistry, Molecular Dynamics Simulation
- Abstract
Hypothesis: Quatsome nanovesicles, formed through the self-assembly of cholesterol (CHOL) and cetyltrimethylammonium bromide (CTAB) in water, have shown long-term stability in terms of size and morphology, while at the same time exhibiting high CHOL-CTAB intermolecular binding energies. We hypothesize that CHOL/CTAB quatsomes are indeed thermodynamically stable nanovesicles, and investigate the mechanism underlying their formation., Experiments: A systematic study was performed to determine whether CHOL/CTAB quatsomes satisfy the experimental requisites of thermodynamically stable vesicles. Coarse-grain molecular dynamics simulations were used to investigate the molecular organization in the vesicle membrane, and the characteristics of the simulated vesicle were corroborated with experimental data obtained by cryo-electron microscopy, small- and wide-angle X-ray scattering, and multi-angle static light scattering., Findings: CHOL/CTAB quatsomes fulfill the requisites of thermodynamically stable nanovesicles, but they do not exhibit the classical membrane curvature induced by a composition asymmetry between the bilayer leaflets, like catanionic nanovesicles. Instead, CHOL/CTAB quatsomes are formed through the association of intrinsically planar bilayers in a faceted vesicle with defects, indicating that distortions in the organization and orientation of molecules can play a major role in the formation of thermodynamically stable nanovesicles., 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 © 2022. Published by Elsevier Inc.)
- Published
- 2023
- Full Text
- View/download PDF
36. Fluorescent Multifunctional Organic Nanoparticles for Drug Delivery and Bioimaging: A Tutorial Review.
- Author
-
Vargas-Nadal G, Köber M, Nsamela A, Terenziani F, Sissa C, Pescina S, Sonvico F, Gazzali AM, Wahab HA, Grisanti L, Olivera ME, Palena MC, Guzman ML, Luciani-Giacobbe LC, Jimenez-Kairuz A, Ventosa N, Ratera I, Belfield KD, and Maoz BM
- Abstract
Fluorescent organic nanoparticles (FONs) are a large family of nanostructures constituted by organic components that emit light in different spectral regions upon excitation, due to the presence of organic fluorophores. FONs are of great interest for numerous biological and medical applications, due to their high tunability in terms of composition, morphology, surface functionalization, and optical properties. Multifunctional FONs combine several functionalities in a single nanostructure (emission of light, carriers for drug-delivery, functionalization with targeting ligands, etc.), opening the possibility of using the same nanoparticle for diagnosis and therapy. The preparation, characterization, and application of these multifunctional FONs require a multidisciplinary approach. In this review, we present FONs following a tutorial approach, with the aim of providing a general overview of the different aspects of the design, preparation, and characterization of FONs. The review encompasses the most common FONs developed to date, the description of the most important features of fluorophores that determine the optical properties of FONs, an overview of the preparation methods and of the optical characterization techniques, and the description of the theoretical approaches that are currently adopted for modeling FONs. The last part of the review is devoted to a non-exhaustive selection of some recent biomedical applications of FONs.
- Published
- 2022
- Full Text
- View/download PDF
37. Hierarchical Quatsome-RGD Nanoarchitectonic Surfaces for Enhanced Integrin-Mediated Cell Adhesion.
- Author
-
Martínez-Miguel M, Castellote-Borrell M, Köber M, Kyvik AR, Tomsen-Melero J, Vargas-Nadal G, Muñoz J, Pulido D, Cristóbal-Lecina E, Passemard S, Royo M, Mas-Torrent M, Veciana J, Giannotti MI, Guasch J, Ventosa N, and Ratera I
- Subjects
- Cell Adhesion, Vitronectin, Oligopeptides pharmacology, Polyethylene Glycols, Surface-Active Agents, Sulfhydryl Compounds, Gold pharmacology, Integrins metabolism, Fibronectins pharmacology, Fibronectins metabolism
- Abstract
The synthesis and study of the tripeptide Arg-Gly-Asp (RGD), the binding site of different extracellular matrix proteins, e.g., fibronectin and vitronectin, has allowed the production of a wide range of cell adhesive surfaces. Although the surface density and spacing of the RGD peptide at the nanoscale have already shown a significant influence on cell adhesion, the impact of its hierarchical nanostructure is still rather unexplored. Accordingly, a versatile colloidal system named quatsomes, based on fluid nanovesicles formed by the self-assembling of cholesterol and surfactant molecules, has been devised as a novel template to achieve hierarchical nanostructures of the RGD peptide. To this end, RGD was anchored on the vesicle's fluid membrane of quatsomes, and the RGD-functionalized nanovesicles were covalently anchored to planar gold surfaces, forming a state of quasi-suspension, through a long poly(ethylene glycol) (PEG) chain with a thiol termination. An underlying self-assembled monolayer (SAM) of a shorter PEG was introduced for vesicle stabilization and to avoid unspecific cell adhesion. In comparison with substrates featuring a homogeneous distribution of RGD peptides, the resulting hierarchical nanoarchitectonic dramatically enhanced cell adhesion, despite lower overall RGD molecules on the surface. The new versatile platform was thoroughly characterized using a multitechnique approach, proving its enhanced performance. These findings open new methods for the hierarchical immobilization of biomolecules on surfaces using quatsomes as a robust and novel tissue engineering strategy.
- Published
- 2022
- Full Text
- View/download PDF
38. Enhanced human T cell expansion with inverse opal hydrogels.
- Author
-
Santos F, Valderas-Gutiérrez J, Pérez Del Río E, Castellote-Borrell M, Rodriguez XR, Veciana J, Ratera I, and Guasch J
- Subjects
- Cell Proliferation, Humans, Porosity, T-Lymphocytes, Hydrogels chemistry, Polyethylene Glycols chemistry
- Abstract
Advanced personalized immunotherapies still have to overcome several biomedical and technical limitations before they become a routine cancer treatment in spite of recent achievements. In adoptive cell therapy (ACT), the capacity to obtain adequate numbers of therapeutic T cells in the patients following ex vivo treatment should be improved. Moreover, the time and costs to produce these T cells should be reduced. In this work, inverse opal (IOPAL) 3D hydrogels consisting of poly(ethylene) glycol (PEG) covalently combined with heparin were engineered to resemble the environment of lymph nodes, where T cells get activated and proliferate. The introduction of an IOPAL strategy allowed a precise control on the porosity of the hydrogels, providing an increase in the proliferation of primary human CD4+ T cells, when compared with state-of-the-art expansion systems. Additionally, the IOPAL hydrogels also showed a superior expansion compared to hydrogels with the same composition, but without the predetermined pore structure. In summary, we have shown the beneficial effect of having an IOPAL architecture in our 3D hydrogels to help achieving large numbers of cells, while maintaining the desired selected phenotypes required for ACT.
- Published
- 2022
- Full Text
- View/download PDF
39. Exploring the impact of the recombinant Escherichia coli strain on defensins antimicrobial activity: BL21 versus Origami strain.
- Author
-
López-Cano A, Martínez-Miguel M, Guasch J, Ratera I, Arís A, and Garcia-Fruitós E
- Subjects
- Animals, Anti-Bacterial Agents chemistry, Antimicrobial Cationic Peptides metabolism, Cattle, Escherichia coli genetics, Escherichia coli metabolism, Gram-Negative Bacteria metabolism, Gram-Positive Bacteria metabolism, Humans, Anti-Infective Agents metabolism, Anti-Infective Agents pharmacology, alpha-Defensins chemistry, alpha-Defensins genetics, alpha-Defensins pharmacology
- Abstract
The growing emergence of microorganisms resistant to antibiotics has prompted the development of alternative antimicrobial therapies. Among them, the antimicrobial peptides produced by innate immunity, which are also known as host defense peptides (HDPs), hold great potential. They have been shown to exert activity against both Gram-positive and Gram-negative bacteria, including those resistant to antibiotics. These HDPs are classified into three categories: defensins, cathelicidins, and histatins. Traditionally, HDPs have been chemically synthesized, but this strategy often limits their application due to the high associated production costs. Alternatively, some HDPs have been recombinantly produced, but little is known about the impact of the bacterial strain in the recombinant product. This work aimed to assess the influence of the Escherichia coli strain used as cell factory to determine the activity and stability of recombinant defensins, which have 3 disulfide bonds. For that, an α-defensin [human α-defensin 5 (HD5)] and a β-defensin [bovine lingual antimicrobial peptide (LAP)] were produced in two recombinant backgrounds. The first one was an E. coli BL21 strain, which has a reducing cytoplasm, whereas the second was an E. coli Origami B, that is a strain with a more oxidizing cytoplasm. The results showed that both HD5 and LAP, fused to Green Fluorescent Protein (GFP), were successfully produced in both BL21 and Origami B strains. However, differences were observed in the HDP production yield and bactericidal activity, especially for the HD5-based protein. The HD5 protein fused to GFP was not only produced at higher yields in the E. coli BL21 strain, but it also showed a higher quality and stability than that produced in the Origami B strain. Hence, this data showed that the strain had a clear impact on both HDPs quantity and quality., (© 2022. The Author(s).)
- Published
- 2022
- Full Text
- View/download PDF
40. o -Carborane-based fluorophores as efficient luminescent systems both as solids and as water-dispersible nanoparticles.
- Author
-
Sinha S, Kelemen Z, Hümpfner E, Ratera I, Malval JP, Jurado JP, Viñas C, Teixidor F, and Núñez R
- Abstract
A set of o -carborane-appended π-conjugated fluorophores and their light-emitting properties in the solid state are reported. The aggregation-induced emission enhancement (AIEE) exhibited for one of the fluorenyl derivatives paved the way to successfully preparing o -carborane-containing organic nanoparticles (NPs) homogeneously dispersed in aqueous media that maintain their luminescence properties. Notably, NPs processed as thin films also show high fluorescence efficiency, suggesting potential optical and optoelectronic applications.
- Published
- 2022
- Full Text
- View/download PDF
41. Methods for the Characterization of Protein Aggregates.
- Author
-
Martínez-Miguel M, Tatkiewicz W, Köber M, Ventosa N, Veciana J, Guasch J, and Ratera I
- Subjects
- Dynamic Light Scattering, Microscopy, Atomic Force methods, Microscopy, Electron, Transmission, Nanoparticles chemistry, Protein Aggregates
- Abstract
The physicochemical characterization of protein aggregates yields an important contribution to further our understanding on many diseases for which the formation of protein aggregates is one of the pathological hallmarks. On the other hand, bacterial inclusion bodies (IBs) have recently been shown to be highly pure proteinaceous aggregates of a few hundred nanometers, produced by recombinant bacteria supporting the biological activities of the embedded polypeptides. Despite the wide spectrum of uses of IBs as functional and biocompatible materials upon convenient engineering, very few is known about their physicochemical properties.In this chapter we present methods for the characterization of protein aggregates as particulate materials relevant to their physicochemical and nanoscale properties.Specifically, we describe the use of dynamic light scattering (DLS) for sizing, nanoparticle tracking analysis for sizing and counting, and zeta potential measurements for the determination of colloidal stability. To study the morphology of protein aggregates we present the use of atomic force microscopy (AFM) and scanning electron microscopy (SEM). Cryo-transmission electron microscopy (cryo-TEM) will be used for the determination of the internal structuration. Moreover, wettability and nanomechanical characterization can be performed using contact angle (CA) and force spectroscopic AFM (FS-AFM) measurements of the proteinaceous nanoparticles, respectively. Finally, the 4'4-dithiodipyridine (DTDP) method is presented as a way of relatively quantifying accessible sulfhydryl groups in the structure of the nanoparticle .The physical principles of the methods are briefly described and examples are given to help clarify capabilities of each technique., (© 2022. Springer Science+Business Media, LLC, part of Springer Nature.)
- Published
- 2022
- Full Text
- View/download PDF
42. Methods for Processing Protein Aggregates into Surfaces.
- Author
-
Martínez-Miguel M, Tatkiewicz W, Köber M, Ventosa N, Veciana J, Guasch J, and Ratera I
- Subjects
- Cell Adhesion, Static Electricity, Surface Properties, Cell Culture Techniques, Protein Aggregates
- Abstract
The processing of inclusion bodies (IBs) into surfaces is of great interest for cell culture applications due to the combined physical and biological cues these particles provide. The arrangement of these IBs into defined and tunable micropatterns can be useful for basic research purposes regarding the mechanical properties needed for cell adhesion and migration, among other responses. There are several approaches that can be used when functionalizing a substrate with IBs, regarding both the strategy used and also the kind of surface-particle interaction. The interaction between surface and IB can be mainly of three types: physisorption, electrostatic or covalent. This interaction can be controlled by depositing an appropriate self-assembled monolayer (SAM) on top of a substrate as an interface. Furthermore, several strategies can be used to immobilize IBs on surfaces in various configurations, like random deposition, micrometric printed geometries or gradient patterns., (© 2022. Springer Science+Business Media, LLC, part of Springer Nature.)
- Published
- 2022
- Full Text
- View/download PDF
43. Polylactide, Processed by a Foaming Method Using Compressed Freon R134a, for Tissue Engineering.
- Author
-
Aguado M, Saldaña L, Pérez Del Río E, Guasch J, Parera M, Córdoba A, Seras-Franzoso J, Cano-Garrido O, Vázquez E, Villaverde A, Veciana J, Ratera I, Vilaboa N, and Ventosa N
- Abstract
Fabricating polymeric scaffolds using cost-effective manufacturing processes is still challenging. Gas foaming techniques using supercritical carbon dioxide (scCO
2 ) have attracted attention for producing synthetic polymer matrices; however, the high-pressure requirements are often a technological barrier for its widespread use. Compressed 1,1,1,2-tetrafluoroethane, known as Freon R134a, offers advantages over CO2 in manufacturing processes in terms of lower pressure and temperature conditions and the use of low-cost equipment. Here, we report for the first time the use of Freon R134a for generating porous polymer matrices, specifically polylactide (PLA). PLA scaffolds processed with Freon R134a exhibited larger pore sizes, and total porosity, and appropriate mechanical properties compared with those achieved by scCO2 processing. PLGA scaffolds processed with Freon R134a were highly porous and showed a relatively fragile structure. Human mesenchymal stem cells (MSCs) attached to PLA scaffolds processed with Freon R134a, and their metabolic activity increased during culturing. In addition, MSCs displayed spread morphology on the PLA scaffolds processed with Freon R134a, with a well-organized actin cytoskeleton and a dense matrix of fibronectin fibrils. Functionalization of Freon R134a-processed PLA scaffolds with protein nanoparticles, used as bioactive factors, enhanced the scaffolds' cytocompatibility. These findings indicate that gas foaming using compressed Freon R134a could represent a cost-effective and environmentally friendly fabrication technology to produce polymeric scaffolds for tissue engineering approaches.- Published
- 2021
- Full Text
- View/download PDF
44. CCL21-loaded 3D hydrogels for T cell expansion and differentiation.
- Author
-
Pérez Del Río E, Santos F, Rodriguez Rodriguez X, Martínez-Miguel M, Roca-Pinilla R, Arís A, Garcia-Fruitós E, Veciana J, Spatz JP, Ratera I, and Guasch J
- Subjects
- Cell Differentiation, Cell Proliferation, Chemokine CCL21, Humans, T-Lymphocytes, Hydrogels, Polyethylene Glycols
- Abstract
Recent achievements in the field of immunotherapy, such as the development of engineered T cells used in adoptive cell therapy, are introducing more efficient strategies to combat cancer. Nevertheless, there are still many limitations. For example, these T cells are challenging to manufacture, manipulate, and control. Specifically, there are limitations in producing the large amounts of therapeutic T cells needed for these therapies in a short period of time and in an economically viable manner. In this study, three-dimensional (3D) poly(ethylene) glycol (PEG) hydrogels covalently combined with low molecular weight heparin are engineered to resemble the lymph nodes, where T cells reproduce. In these hydrogels, PEG provides the needed structural and mechanical properties, whereas heparin is used as an anchor for the cytokine CCL21, which is present in the lymph nodes, and can affect cell migration and proliferation. The 3D structure of the hydrogel in combination with its loading capacity result in an increased primary human CD4
+ T cell proliferation compared to the state-of-the-art expansion systems consisting of artificial antigen presenting cells. Thus, we present a new tool for adoptive cell therapy to help achieving the large numbers of cells required for therapy of selected phenotypes targeted against cancer cells, by mimicking the lymph nodes., (Copyright © 2020 Elsevier Ltd. All rights reserved.)- Published
- 2020
- Full Text
- View/download PDF
45. Stable anchoring of bacteria-based protein nanoparticles for surface enhanced cell guidance.
- Author
-
Martínez-Miguel M, Kyvik AR, M Ernst L, Martínez-Moreno A, Cano-Garrido O, Garcia-Fruitós E, Vazquez E, Ventosa N, Guasch J, Veciana J, Villaverde A, and Ratera I
- Subjects
- Humans, Molecular Structure, Optical Imaging, Particle Size, Surface Properties, Tumor Cells, Cultured, Bacterial Proteins chemistry, Escherichia coli chemistry, Lactococcus lactis chemistry, Nanoparticles chemistry
- Abstract
In tissue engineering, biological, physical, and chemical inputs have to be combined to properly mimic cellular environments and successfully build artificial tissues which can be designed to fulfill different biomedical needs such as the shortage of organ donors or the development of in vitro disease models for drug testing. Inclusion body-like protein nanoparticles (pNPs) can simultaneously provide such physical and biochemical stimuli to cells when attached to surfaces. However, this attachment has only been made by physisorption. To provide a stable anchoring, a covalent binding of lactic acid bacteria (LAB) produced pNPs, which lack the innate pyrogenic impurities of Gram-negative bacteria like Escherichia coli, is presented. The reported micropatterns feature a robust nanoscale topography with an unprecedented mechanical stability. In addition, they are denser and more capable of influencing cell morphology and orientation. The increased stability and the absence of pyrogenic impurities represent a step forward towards the translation of this material to a clinical setting.
- Published
- 2020
- Full Text
- View/download PDF
46. An Enantiopure Propeller-Like Trityl-Brominated Radical: Bringing Together a High Racemization Barrier and an Efficient Circularly Polarized Luminescent Magnetic Emitter.
- Author
-
Mayorga-Burrezo P, Jiménez VG, Blasi D, Parella T, Ratera I, Campaña AG, and Veciana J
- Abstract
A new persistent organic free radical has been synthetized with Br atoms occupying the ortho- and para-positions of a trityl core. After the isolation of its two propeller-like atropisomers, Plus (P) and minus (M), their absolute configurations were assigned by a combination of theoretical and experimental data. Remarkably, no hints of racemization were observed up to 60 °C for more than two hours, due to the higher steric hindrance imposed by the bulky Br atoms. Therefore, when compared to its chlorinated homologue (t
1/2 =18 s at 60 °C), an outstanding stability against racemization was achieved. A circularly polarized luminescence (CPL) response of both enantiomers was detected. This free radical shows a satisfactory luminescent dissymmetry factor (|glum (592 nm)|≈0.7×10-3 ) despite its pure organic nature and low luminescence quantum yield (LQY). Improved organic magnetic CPL emitters derived from the reported structure can be envisaged thanks to the wide possibilities that Br atoms at para-positions offer for further functionalization., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)- Published
- 2020
- Full Text
- View/download PDF
47. Organic Free Radicals as Circularly Polarized Luminescence Emitters.
- Author
-
Mayorga Burrezo P, Jiménez VG, Blasi D, Ratera I, Campaña AG, and Veciana J
- Abstract
Chiroptical properties of two chiral atropisomers of propeller-like trityl-based radical derivatives have been analyzed. A new absolute configuration (AC) assignment has been made, according to the combination of experimental and theoretical data. In this sense, their ACs have been determined through the comparison of the Cotton effects recorded by electronic circular dichroism (ECD) with the theoretical ECD of the open shell structures obtained by TD-DFT calculations. Finally, their circularly polarized luminescence (CPL) responses have been addressed. Remarkably, this is the first description of organic free radicals as intrinsic CPL emitters. Opposite signed CPL has been detected for each pair of conformers, with acceptable luminescent dissymmetry factors (|g
lum |≈0.5-0.8×10-3 ) considering their pure organic nature. In fact, highly efficient chiral emissions have been demonstrated, according to the comparison of |glum | with their respective absorption anisotropy factors (|gabs |). This pioneering study lays the foundations for the optimization of new magnetically active organic chiral emitters., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)- Published
- 2019
- Full Text
- View/download PDF
48. High-Throughput Cell Motility Studies on Surface-Bound Protein Nanoparticles with Diverse Structural and Compositional Characteristics.
- Author
-
Tatkiewicz WI, Seras-Franzoso J, García-Fruitós E, Vazquez E, Kyvik AR, Ventosa N, Guasch J, Villaverde A, Veciana J, and Ratera I
- Abstract
Eighty areas with different structural and compositional characteristics made of bacterial inclusion bodies formed by the fibroblast growth factor (FGF-IBs) were simultaneously patterned on a glass surface with an evaporation-assisted method that relies on the coffee-drop effect. The resulting surface patterned with these protein nanoparticles enabled to perform a high-throughput study of the motility of NIH-3T3 fibroblasts under different conditions including the gradient steepness, particle concentrations, and area widths of patterned FGF-IBs, using for the data analysis a methodology that includes "heat maps". From this analysis, we observed that gradients of concentrations of surface-bound FGF-IBs stimulate the total cell movement but do not affect the total net distances traveled by cells. Moreover, cells tend to move toward an optimal intermediate FGF-IB concentration (i.e., cells seeded on areas with high IB concentrations moved toward areas with lower concentrations and vice versa, reaching the optimal concentration). Additionally, a higher motility was obtained when cells were deposited on narrow and highly concentrated areas with IBs. FGF-IBs can be therefore used to enhance and guide cell migration, confirming that the decoration of surfaces with such IB-like protein nanoparticles is a promising platform for regenerative medicine and tissue engineering.
- Published
- 2019
- Full Text
- View/download PDF
49. Functionalization of polyacrylamide for nanotrapping positively charged biomolecules.
- Author
-
Davydova N, Rodriguez XR, Blázquez C, Gómez A, Perevyazko I, Guasch J, Sergeev V, Laukhina E, Ratera I, and Veciana J
- Abstract
Engineering new materials which are capable of trapping biomolecules in nanoscale quantities, is crucial in order to achieve earlier diagnostics in different diseases. This article demonstrates that using free radical copolymerization, polyacrylamide can be successfully functionalized with specific synthons for nanotrapping positively charged molecules, such as numerous proteins, through electrostatic interactions due to their negative charge. Specifically, two functional random copolymers, acrylamide/acrylic acid (1) and acrylamide/acrylic acid/ N -(pyridin-4-yl-methyl)acrylamide (2), whose negative net charges differ in their water solutions, were synthetized and their ability to trap positively charged proteins was studied using myoglobin as a proof-of-concept example. In aqueous solutions, copolymer 1, whose net charge for a 100 chain fragment ( Q
pH 6 / M ) is -1.323 × 10-3 , interacted with myoglobin forming a stable monodisperse nanosuspension. In contrast, copolymer 2, whose value of QpH 6 / M equals -0.361 × 10-3 , was not able to form stable particles with myoglobin. Nevertheless, thin films of both copolymers were grown using a dewetting process, which exhibited nanoscale cavities capable of trapping different amounts of myoglobin, as demonstrated by bimodal AFM imaging. The simple procedures used to build protein traps make this engineering approach promising for the development of new materials for biomedical applications where trapping biomolecules is required., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2019
- Full Text
- View/download PDF
50. Correction: Pulling lipid tubes from supported bilayers unveils the underlying substrate contribution to the membrane mechanics.
- Author
-
Gumí-Audenis B, Costa L, Ferrer-Tasies L, Ratera I, Ventosa N, Sanz F, and Giannotti MI
- Abstract
Correction for 'Pulling lipid tubes from supported bilayers unveils the underlying substrate contribution to the membrane mechanics' by Marina I. Giannotti et al., Nanoscale, 2018, 10, 14763-14770.
- Published
- 2018
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.