Publications

This study presents a novel protocol to quantify the surface distribution, penetration depth and concentration of reactive oxygen and nitrogen species (RONS) generated by plasma in biocompatible hydrogels, serving as tissue surrogates. Using colorimetric probes, we visualized and quantified RONS interaction through color intensity analysis. Two types of hydrogels were used-agarose and gelatin-at different concentrations, to study how composition and concentration affect the interaction of plasma-generated RONS. The results show that the surface distribution and penetration depth of RONS increase with treatment time and depend on the chemical structure and concentration of the hydrogel. This methodology offers a reproducible, animal-free approach to optimize plasma-based therapies by enabling precise assessment of ROS and RNS behavior in 3D tissue-like environments.

JTD Keywords: Agarose, Cold atmospheric plasma, Gelatin, Plasma medicine, Tissue models

Hydrogen peroxide (H2O2) is a key reactive species in biological, environmental, and industrial systems, creating a demand for robust, sustainable, and tunable sensing materials. Here, we report a green, simple in situ strategy to fabricate magnetically responsive catalytic chitosan-agarose hydrogels with tunable nano-microstructure and transport properties. Fe3O4 nanoparticles are generated directly within chitosan-agarose hydrogel networks using chloride- and sulfate-based iron precursors, enabling controlled modulation of nanoparticle size distribution, crystallographic plane exposure, and magnetic response without surfactants or organic solvents. We demonstrate that the choice of iron precursor governs nanoparticle nucleation kinetics and interfacial interactions with the biopolymer matrix, leading to distinct microstructural architectures that directly impact mechanical stiffness, swelling behavior, and magnetic properties. Importantly, the embedded Fe3O4 nanoparticles exhibit intrinsic peroxidase-like catalytic activity, allowing the hydrogels to function as a solid-state nanozyme platform for colorimetric H2O2 detection. Beyond static performance, we show that external magnetic fields dynamically reconfigure hydrogel properties providing reversible, field-controlled regulation of catalytic activity and sensing sensitivity. The optimized hydrogels display linear H2O2 detection up to 100 mu M with sub-micromolar detection limits (< 1 mu M), while offering key materials-level advantages including reusability, structural stability, and facile magnetic manipulation. This work establishes a simple approach for integrating nanozyme catalysis, magnetic actuation, and sustainable biopolymer matrices, offering a broadly applicable platform for magnetically tunable catalytic materials and responsive sensing systems.

JTD Keywords: Chitosan-agarose nanocomposites, Colorimetric detection, Fe3o4 nanozymes, Nanoparticles, Peroxidase-like activity, Sustainable biosensors

The efficient degradation of organic pollutants is critical for environmental sustainability, driving the search for eco-friendly catalytic materials. Biopolymer-based magnetic hydrogels are promising candidates, though current systems often face challenges such as poor mechanical stability, uneven nanocatalyst distribution, and complex synthesis. Here, we present a green, simple, and scalable method for fabricating chitosan-agarose dual-network hydrogels incorporating Fe3O4 nanoparticles (NPs) synthesized in situ from two iron salts. This strategy ensures uniform NPs dispersion within a mechanically robust and biocompatible matrix, enabling multifunctional hydrogels that combine catalytic efficiency, magnetic responsiveness, and reusability. The Fe3O4 content was systematically varied to tune the hydrogel's physicochemical, mechanical, and magnetic properties. Structural characterization by X-ray diffraction and transmission electron microscopy confirmed successful in situ Fe3O4 NPs formation, with differences in size and morphology depending on the iron precursor. Rheological analysis showed increased stiffness with higher Fe3O4 content, while swelling tests revealed reduced water uptake due to pore filling. Catalytic performance was evaluated using model pollutants achieving up to 94 % degradation within 90 min under mild conditions. These nanocomposite hydrogels offer a sustainable, magnetically recoverable, and reusable platform for efficient pollutant removal, highlighting the synergistic advantages of dualbiopolymer matrices and in situ nanocatalyst formation for water remediation.

JTD Keywords: Catalytic and magnetic propertie, Chitosan-agarose hydrogel, Nanoparticles, Remova

Visual impairments are a critical medical hurdle to be addressed in modern society. Müller glia (MG) have regenerative potential in the retina in lower vertebrates, but not in mammals. However, in mice, in vivo cell fusion between MG and adult stem cells forms hybrids that can partially regenerate ablated neurons.We used organotypic cultures of human retina and preparations of dissociated cells to test the hypothesis that cell fusion between human MG and adult stem cells can induce neuronal regeneration in human systems. Moreover, we established a microinjection system for transplanting human retinal organoids to demonstrate hybrid differentiation.We first found that cell fusion occurs between MG and adult stem cells, in organotypic cultures of human retina as well as in cell cultures. Next, we showed that the resulting hybrids can differentiate and acquire a proto-neural electrophysiology profile when the Wnt/beta-catenin pathway is activated in the adult stem cells prior fusion. Finally, we demonstrated the engraftment and differentiation of these hybrids into human retinal organoids.We show fusion between human MG and adult stem cells, and demonstrate that the resulting hybrid cells can differentiate towards neural fate in human model systems. Our results suggest that cell fusion-mediated therapy is a potential regenerative approach for treating human retinal dystrophies.This work was supported by La Caixa Health (HR17-00231), Velux Stiftung (976a) and the Ministerio de Ciencia e Innovación, (BFU2017-86760-P) (AEI/FEDER, UE), AGAUR (2017 SGR 689, 2017 SGR 926).Published by Elsevier B.V.

JTD Keywords: cell fusion, expression, fusion, ganglion-cells, in-vitro, mouse, müller glia, neural differentiation, organoids, regeneration, retina regeneration, stem cells, stromal cells, transplantation, 4',6 diamidino 2 phenylindole, 5' nucleotidase, Agarose, Alcohol, Arpe-19 cell line, Article, Beta catenin, Beta tubulin, Bone-marrow-cells, Bromophenol blue, Buffer, Calcium cell level, Calcium phosphate, Calretinin, Canonical wnt signaling, Cd34 antigen, Cell culture, Cell fusion, Cell viability, Coculture, Complementary dna, Confocal microscopy, Cornea transplantation, Cryopreservation, Cryoprotection, Crystal structure, Current clamp technique, Dimethyl sulfoxide, Dodecyl sulfate sodium, Edetic acid, Electrophysiology, Endoglin, Fetal bovine serum, Fibroblast growth factor 2, Flow cytometry, Fluorescence activated cell sorting, Fluorescence intensity, Glyceraldehyde 3 phosphate dehydrogenase, Glycerol, Glycine, Hoe 33342, Immunofluorescence, Immunohistochemistry, Incubation time, Interleukin 1beta, Lentivirus vector, Matrigel, Mercaptoethanol, Microinjection, Mueller cell, Müller glia, N methyl dextro aspartic acid, Nerve cell differentiation, Neural differentiation, Nitrogen, Nonhuman, Organoids, Paraffin, Paraffin embedding, Paraformaldehyde, Patch clamp technique, Penicillin derivative, Phenolsulfonphthalein, Phenotype, Phosphate buffered saline, Phosphoprotein phosphatase inhibitor, Polyacrylamide gel electrophoresis, Potassium chloride, Povidone iodine, Promoter region, Proteinase inhibitor, Real time polymerase chain reaction, Receptor type tyrosine protein phosphatase c, Restriction endonuclease, Retina, Retina dystrophy, Retina regeneration, Retinol, Rhodopsin, Rna extraction, Stem cell, Stem cells, Subcutaneous fat, Tunel assay, Visual impairment, Western blotting