RESUMEN
This study presents a novel biotechnological approach for creating water vapor-resistant cryogels with improved integrity. Rice straw cellulose was transformed into nanofibrils through TEMPO-mediated oxidation and high-pressure homogenization. The resulting cryogels remained firm even when immersed in aqueous media, whose pores were used by live cell to deposit polyhydroxyalkanoate (PHA) particles inside them. This novel method allowed the compatibilization of PHA within the cellulosic fibers. As a consequence, the water sorption capacity was decreased by up to 6 times having just 4 % of PHA compared to untreated cryogels, preserving the cryogel density and elasticity. Additionally, this technique can be adapted to various bacterial strains and PHA types, allowing for further optimization. It was demonstrated that the amount and type of PHA (medium chain length and small chain length-PHA) used affects the properties for the cryogels, especially the water vapor sorption behavior and the compressive strength. Compared to traditional coating methods, this cell-mediated approach not only allows to distribute PHA on the surface of the cryogel, but also ensures polymer penetration throughout the cryogel due to bacterial self-movement. This study opens doors for creating cryogels with tunable water vapor sorption and other additional functionalities through the use of specialized PHA variants.
Asunto(s)
Celulosa , Criogeles , Oryza , Polihidroxialcanoatos , Polihidroxialcanoatos/química , Criogeles/química , Oryza/química , Celulosa/química , Agua/química , Vapor , Óxidos N-Cíclicos/química , Fuerza CompresivaRESUMEN
Uncontrolled hemorrhage stands as the primary cause of potentially preventable deaths following traumatic injuries in both civilian and military populations. Addressing this critical medical need requires the development of a hemostatic material with rapid hemostatic performance and biosafety. This work describes the engineering of a chitosan-based cryogel construct using thermo-assisted cross-linking with α-ketoglutaric acid after freeze-drying. The resulting cryogel exhibited a highly interconnected macro-porous structure with low thermal conductivity, exceptional mechanical properties, and great fluid absorption capacity. Notably, assessments using rabbit whole blood in vitro, as well as rat liver volume defect and femoral artery injury models simulating severe bleeding, showed the remarkable hemostatic performance of the chitosan cryogel. Among the cryogel variants with different chitosan molecular weights, the 150 kDa one demonstrated superior hemostatic efficacy, reducing blood loss and hemostasis time by approximately 73 % and 63 % in the hepatic model, and by around 60 % and 68 %, in the femoral artery model. Additionally, comprehensive in vitro and in vivo evaluations underscored the good biocompatibility of the chitosan cryogel. Taken together, these results strongly indicate that the designed chitosan cryogel configuration holds significant potential as a safe and rapid hemostatic material for managing severe hemorrhage.
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Quitosano , Criogeles , Hemorragia , Hemostáticos , Quitosano/química , Quitosano/farmacología , Criogeles/química , Animales , Conejos , Hemorragia/terapia , Hemorragia/tratamiento farmacológico , Hemostáticos/química , Hemostáticos/farmacología , Ratas , Masculino , Ratas Sprague-Dawley , Arteria Femoral/lesiones , Porosidad , Hígado/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Reactivos de Enlaces Cruzados/química , Hemostasis/efectos de los fármacosRESUMEN
Objective.Cryogel microcarriers made of poly(ethylene glycol) diacrylate and 3-sulfopropyl acrylate have the potential to act as delivery vehicles for long-term retention of neurotrophic factors (NTFs) in the brain. In addition, they can potentially enhance stem cell-derived dopaminergic (DAergic) cell replacement strategies for Parkinson's disease (PD), by addressing the limitations of variable survival and poor differentiation of the transplanted precursors due to neurotrophic deprivation post-transplantation in the brain. In this context, to develop a proof-of-concept, the aim of this study was to determine the efficacy of glial cell line-derived NTF (GDNF)-loaded cryogel microcarriers by assessing their impact on the survival of, and reinnervation by, primary DAergic grafts after intra-striatal delivery in Parkinsonian rat brains.Approach.Rat embryonic day 14 ventral midbrain cells were transplanted into the 6-hydroxydopamine-lesioned striatum either alone, or with GDNF, or with unloaded cryogel microcarriers, or with GDNF-loaded cryogel microcarriers.Post-mortem, GDNF and tyrosine hydroxylase immunostaining were used to identify retention of the delivered GDNF within the implanted cryogel microcarriers, and to identify the transplanted DAergic neuronal cell bodies and fibres in the brains, respectively.Main results.We found an intact presence of GDNF-stained cryogel microcarriers in graft sites, indicating their ability for long-term retention of the delivered GDNF up to 4 weeks in the brain. This resulted in an enhanced survival (1.9-fold) of, and striatal reinnervation (density & volume) by, the grafted DAergic neurons, in addition to an enhanced sprouting of fibres within graft sites.Significance.This data provides an important proof-of-principle for the beneficial effects of neurotrophin-loaded cryogel microcarriers on engraftment of cells in the context of cell replacement therapy in PD. For clinical translation, further studies will be needed to assess the impact of cryogel microcarriers on the survival and differentiation of stem cell-derived DAergic precursors in Parkinsonian rat brains.
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Criogeles , Neuronas Dopaminérgicas , Factor Neurotrófico Derivado de la Línea Celular Glial , Animales , Factor Neurotrófico Derivado de la Línea Celular Glial/administración & dosificación , Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Ratas , Criogeles/administración & dosificación , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/trasplante , Enfermedad de Parkinson/terapia , Ratas Sprague-Dawley , Modelos Animales de Enfermedad , Células Cultivadas , MasculinoRESUMEN
Wound healing represents a complex biological process crucial for tissue repair and regeneration. In recent years, biomaterial-based scaffolds loaded with bioactive compounds have emerged as promising therapeutic strategies to accelerate wound healing. In this study, we investigated the properties and wound healing effects of cryogels loaded with calcium peroxide (CP) and berberine (BB). The cryogels were synthesized through a cryogenic freezing technique and displayed pore diameters of 83 ± 39 µm, with porosity exceeding 90%. Following 20 days of degradation, the percentage of remaining weight for GPC and GPC-CP-BB cryogels was determined to be 12.42 ± 2.45% and 10.78 ± 2.08%, respectively. Moreover, the swelling ratios after 3 minutes for GPC and GPC-CP-BB were found to be 22.10 ± 0.05 and 21.00 ± 0.07, respectively. In vitro investigations demonstrated the cytocompatibility of the cryogels, with sufficient adhesion and proliferation of fibroblast (NIH-3T3) cells observed on the scaffolds, along with their hemocompatibility. Furthermore, the cryogels exhibited sustained release kinetics of both calcium peroxide and berberine, ensuring prolonged therapeutic effects at the wound site. In vivo assessment using a rat model of full-thickness skin wounds demonstrated accelerated wound closure rates in animals treated with the GPC-CP-BB scaffold compared to controls. Histological analysis revealed enhanced granulation tissue formation, re-epithelialization, and collagen deposition in the GPC-CP-BB group. Overall, our findings suggest that the scaffold loaded with CP and BB holds great promise as a therapeutic approach for promoting wound healing. Its multifaceted properties offer a multifunctional platform for localized delivery of therapeutic agents while providing mechanical support and maintaining a favorable microenvironment for tissue regeneration.
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Berberina , Criogeles , Peróxidos , Cicatrización de Heridas , Berberina/química , Berberina/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Criogeles/química , Ratones , Ratas , Células 3T3 NIH , Peróxidos/química , Peróxidos/farmacología , Proliferación Celular/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/síntesis química , Ratas Sprague-Dawley , Masculino , PorosidadRESUMEN
The main goal of our study is to demonstrate the applicability of the PPy-cryogel-modified electrodes for electrochemical detection of DNA. First, a polysaccharide-based cryogel was synthesized. This cryogel was then used as a template for chemical polypyrrole synthesis. This prepared polysaccharide-based conductive cryogel was used for electrochemical biosensing on DNA. Carrageenan (CG) and sodium alginate (SA) polysaccharides, which stand out as biocompatible materials, were used in cryogel synthesis. Electron transfer was accelerated by polypyrrole (PPy) synthesized in cryogel networks. A 2B pencil graphite electrode with a diameter of 2.00 mm was used as a working electrode. The prepared polysaccharide solution was dropped onto a working electrode as a support material to improve the immobilization capacity of biomolecules and frozen to complete the cryogelation step. PPy synthesis was performed on the electrodes whose cryogelation process was completed. In addition, the structures of cryogels synthesized on the electrode surface were characterized by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Surface characterization of the modified electrodes was performed by energy-dispersive X-ray spectroscopy (EDX) analysis. Electrochemical determination of fish sperm DNA (fsDNA) was performed using a PPy-cryogel-modified electrode. The use of a porous 3D cryogel intermediate material enhanced the signal by providing a large surface area for the synthesis of PPy and increasing the biomolecule immobilization capacity. The detection limit was 0.98 µg mL-1 in the fsDNA concentration range 2.5-20 µg mL-1. The sensitivity of the DNA biosensor was estimated to 14.8 µA mM-1 cm-2. The stability of the biosensor under certain storage conditions was examined and observed to remain 66.95% up to 45 days.
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Alginatos , Técnicas Biosensibles , Criogeles , ADN , Técnicas Electroquímicas , ADN/química , Técnicas Electroquímicas/métodos , Animales , Criogeles/química , Alginatos/química , Técnicas Biosensibles/métodos , Electrodos , Peces , Masculino , Carragenina/química , Polisacáridos/química , Polisacáridos/análisis , Pirroles/química , Espermatozoides/química , Límite de Detección , PolímerosRESUMEN
Mucogingival surgery has been widely used in soft gingival tissue augmentation in which autografts are predominantly employed. However, the autografts face grand challenges, such as scarcity of palatal donor tissue and postoperative discomfort. Therefore, development of alternative soft tissue substitutes has been an imperative need. Here, we engineered an interconnected porous bovine serum albumin methacryloyl (BSAMA: B, as a drug carrier and antioxidant)/gelatin methacryloyl (GelMA: G, as a biocompatible collagen-like component)-based cryogel with L-Arginine (Arg) loaded as an angiogenic molecule, which could serve as a promising gingival tissue biohybrid scaffold. BG@Arg cryogels featured macroporous architecture, biodegradation, sponge-like properties, suturability, and sustained Arg release. Moreover, BG@Arg cryogels promoted vessel formation and collagen deposition which play an important role in tissue regeneration. Most interestingly, BG@Arg cryogels were found to enhance antioxidant effects. Finally, the therapeutic effect of BG@Arg on promoting tissue regeneration was confirmed in rat full-thickness skin and oral gingival defect models. In vivo results revealed that BG@Arg2 could promote better angiogenesis, more collagen production, and better modulation of inflammation, as compared to a commercial collagen membrane. These advantages might render BG@Arg cryogels a promising alternative to commercial collagen membrane products and possibly autografts for soft gingival tissue regeneration.
Asunto(s)
Arginina , Criogeles , Gelatina , Encía , Regeneración , Albúmina Sérica Bovina , Andamios del Tejido , Criogeles/química , Animales , Arginina/química , Arginina/farmacología , Ratas , Gelatina/química , Regeneración/efectos de los fármacos , Albúmina Sérica Bovina/química , Andamios del Tejido/química , Cicatrización de Heridas/efectos de los fármacos , Metacrilatos/química , Bovinos , Porosidad , Masculino , Antioxidantes/farmacología , Antioxidantes/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Ingeniería de Tejidos/métodos , Ratas Sprague-DawleyRESUMEN
Trauma or repeated damage to joints can result in focal cartilage defects, significantly elevating the risk of osteoarthritis. Damaged cartilage has an inherently limited self-healing capacity and remains an urgent unmet clinical need. Consequently, there is growing interest in biodegradable hydrogels as potential scaffolds for the repair or reconstruction of cartilage defects. Here, we developed a biodegradable and macroporous hybrid double-network (DN) cryogel by combining two independently cross-linked networks of multiarm polyethylene glycol (PEG) acrylate and alginate.Hybrid DN cryogels are formed using highly biocompatible click reactions for the PEG network and ionic bonding for the alginate network. By judicious selection of various structurally similar cross-linkers to form the PEG network, we can generate hybrid DN cryogels with customizable degradation kinetics. The resulting PEG-alginate hybrid DN cryogels have an interconnected macroporous structure, high mechanical strength, and rapid swelling kinetics. The interconnected macropores in the cryogels support efficient mesenchymal stem cell infiltration at a high density. Finally, we demonstrate that PEG-alginate hybrid DN cryogels allow sustained release of chondrogenic growth factors and support chondrogenic differentiation of mouse mesenchymal stem cells. This study provides a novel method to generate macroporous hybrid DN cryogels with customizable degradation rates and a potential scaffold for cartilage tissue engineering.
Asunto(s)
Alginatos , Materiales Biocompatibles , Criogeles , Ensayo de Materiales , Polietilenglicoles , Ingeniería de Tejidos , Criogeles/química , Alginatos/química , Polietilenglicoles/química , Materiales Biocompatibles/química , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/farmacología , Porosidad , Animales , Ratones , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Reactivos de Enlaces Cruzados/química , Cartílago , Tamaño de la Partícula , Andamios del Tejido/química , Condrogénesis/efectos de los fármacosRESUMEN
The effective management of deep skin wounds remains a significant healthcare challenge that often deteriorates with bacterial infection, oxidative stress, tissue necrosis, and excessive production of wound exudate. Current medical approaches, including traditional wound dressing materials, cannot effectively address these issues. There is a great need to engineer advanced and multifunctional wound dressings to address this multifaceted problem effectively. Herein, a rationally designed composite cryogel composed of a Copper Metal-Organic Framework (Cu-MOF), tannic acid (TA), polyvinyl alcohol (PVA), and zein protein has been developed by freeze-thaw technique. Cryogels display a remarkable swelling capacity attributed to their interconnected microporous morphology. Moreover, dynamic mechanical behaviour with the characteristics of potent antimicrobial, antioxidant, and biodegradation makes it a desirable wound dressing material. It was further confirmed that the material is highly biocompatible and can release TA and copper ions in a controlled manner. In-vivo skin irritation in a rat model demonstrated that composite cryogel did not provoke any irritation/inflammation when applied to the skin of a healthy recipient. In a deep wound model, the composite cryogel significantly accelerates the wound healing rate. These findings highlight the multifunctional nature of composite cryogels and their promising potential for clinical applications as advanced wound dressings.
Asunto(s)
Cobre , Criogeles , Estructuras Metalorgánicas , Piel Artificial , Taninos , Cicatrización de Heridas , Criogeles/química , Taninos/química , Taninos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Cobre/química , Ratas , Piel/efectos de los fármacos , Piel/lesiones , Piel/patología , Piel/metabolismo , Humanos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Vendajes , Masculino , PolifenolesRESUMEN
Traditional ice is usually employed to preserve food freshness and extend shelf life. However, ice cannot bear repeated freeze - thaw cycles during the transportation and retailing process, resulting in microbial cross-contamination and spoilage of foods. Herein, succinoglycan riclin was oxidated (RO) and crosslinked with gelatin (Ge), the Ge-RO cryogels were prepared via Schiff base reaction and three freeze - thaw cycles. The Ge-RO cryogels showed improved storage modulus (G') and thermal stability compared with pure gelatin hydrogel. The polymer framework of Ge-RO gels exhibited stable properties against ice crystals destructions during nine freeze - thaw treatments. During the storage and repeated freeze - thaw treatments of shrimps, Ge-RO cryogels exhibited a remarkable preservation effect on shrimps, and their freshness was evaluated using an electronic nose technique equipped with ten sensors. The results demonstrated that the shrimp muscle preserved in ice generated off-odors and resulted in high sensor responses. The sensor responses were reduced sharply of shrimps preserved in cryogels. Moreover, 1H NMR-based metabolomics analysis revealed that shrimps in Ge-RO cryogels group reversed the metabolic perturbations compared with the traditional ice group, the metabolic pathways were related to energy metabolism, nucleotide metabolism, and amino acid metabolism, which provide new clues to the freshness of shrimps. Furthermore, RO exhibited superior antimicrobial activity against E. coli and S. aureus microorganisms. Thus, the crosslinked cryogels are potentially applicable to food preservation, offering sustainable and reusable solutions against traditional ice.
Asunto(s)
Criogeles , Conservación de Alimentos , Gelatina , Animales , Gelatina/química , Conservación de Alimentos/métodos , Criogeles/química , Hielo , Penaeidae , Oxidación-Reducción , Mariscos/microbiología , Congelación , Nariz Electrónica , Almacenamiento de Alimentos/métodos , Escherichia coli/efectos de los fármacosRESUMEN
Biobased porous hydrogels enriched with phytocompounds-rich herbal extracts have aroused great interest in recent years, especially in healthcare. In this study, new macroporous hybrid cryogel constructs comprising thiourea-containing chitosan (CSTU) derivative and a Hypericum perforatum L. extract (HYPE), commonly known as St John's wort, were prepared by a facile one-pot ice-templating strategy. Benefiting from the strong interactions between the functional groups of the CSTU matrix and those of polyphenols in HYPE, the hybrid cryogels possess excellent liquid absorption capacity, mechanical resilience, antioxidant performance, and a broad spectrum of antibacterial activity simultaneously. Thus, owing to their design, the hybrid constructs exhibit an interconnected porous architecture with the ability to absorb over 33 and 136 times their dry weight, respectively, when contacted with a phosphate buffer solution (pH 7.4) and an acidic aqueous solution (pH 2). These cryogel constructs have extremely high compressive strengths ranging from 839 to 1045 kPa and withstand elevated strains of over 70% without developing fractures. Moreover, the water-swollen hybrid cryogels with the highest HYPE content revealed a complete and instant shape recovery after uniaxial compression. The incorporation of HYPE into CSTU cryogels enabled substantial improvement in scavenging reactive oxygen species and an expanded antibacterial spectrum toward multiple pathogens, including Gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis), Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), and fungi (Candida albicans). Cell viability experiments demonstrated the cytocompatibility of the 3D cryogel constructs, which did not induce changes in the fibroblast morphology. This work showcases a simple and effective strategy to immobilize HYPE extracts on CSTU 3D networks, allowing the development of novel multifunctional platforms with promising potential in hemostasis, wound dressing, and dermal regeneration scaffolds.
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Antibacterianos , Materiales Biocompatibles , Quitosano , Criogeles , Hypericum , Extractos Vegetales , Quitosano/química , Quitosano/farmacología , Hypericum/química , Criogeles/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Animales , Ratones , Porosidad , Staphylococcus aureus/efectos de los fármacos , Fuerza Compresiva , Antioxidantes/farmacología , Antioxidantes/química , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrolloRESUMEN
Limited treatments and a lack of appropriate animal models have spurred the study of scaffolds to mimic lung disease in vitro. Decellularized human lung and its application in extracellular matrix (ECM) hydrogels has advanced the development of these lung ECM models. Controlling the biochemical and mechanical properties of decellularized ECM hydrogels continues to be of interest due to inherent discrepancies of hydrogels when compared to their source tissue. To optimize the physiologic relevance of ECM hydrogel lung models without sacrificing the native composition we engineered a binary fabrication system to produce a Hybridgel composed of an ECM hydrogel reinforced with an ECM cryogel. Further, we compared the effect of ECM-altering disease on the properties of the gels using elastin poor Chronic Obstructive Pulmonary Disease (COPD) vs non-diseased (ND) human lung source tissue. Nanoindentation confirmed the significant loss of elasticity in hydrogels compared to that of ND human lung and further demonstrated the recovery of elastic moduli in ECM cryogels and Hybridgels. These findings were supported by similar observations in diseased tissue and gels. Successful cell encapsulation, distribution, cytotoxicity, and infiltration were observed and characterized via confocal microscopy. Cells were uniformly distributed throughout the Hybridgel and capable of survival for 7 days. Cell-laden ECM hybridgels were found to have elasticity similar to that of ND human lung. Compositional investigation into diseased and ND gels indicated the conservation of disease-specific elastin to collagen ratios. In brief, we have engineered a composited ECM hybridgel for the 3D study of cell-matrix interactions of varying lung disease states that optimizes the application of decellularized lung ECM materials to more closely mimic the human lung while conserving the compositional bioactivity of the native ECM. STATEMENT OF SIGNIFICANCE: The lack of an appropriate disease model for the study of chronic lung diseases continues to severely inhibit the advancement of treatments and preventions of these otherwise fatal illnesses due to the inability to recapture the biocomplexity of pathologic cell-ECM interactions. Engineering biomaterials that utilize decellularized lungs offers an opportunity to deconstruct, understand, and rebuild models that highlight and investigate how disease specific characteristics of the extracellular environment are involved in driving disease progression. We have advanced this space by designing a binary fabrication system for a ECM Hybridgel that retains properties from its source material required to observe native matrix interactions. This design simulates a 3D lung environment that is both mechanically elastic and compositionally relevant when derived from non-diseased tissue and pathologically diminished both mechanically and compositionally when derived from COPD tissue. Here we describe the ECM hybridgel as a model for the study of cell-ECM interactions involved in COPD.
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Pulmón , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Enfermedad Pulmonar Obstructiva Crónica/patología , Pulmón/patología , Matriz Extracelular Descelularizada/química , Matriz Extracelular Descelularizada/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Matriz Extracelular/química , Modelos Biológicos , Criogeles/química , AnimalesRESUMEN
The ordered arrangement of cells and extracellular matrix facilitates the seamless transmission of electrical signals along axons in the spinal cord and peripheral nerves. Therefore, restoring tissue geometry is crucial for neural regeneration. This study presents a novel method using proteins derived from the human amniotic membrane, which is modified with photoresponsive groups, to produce cryogels with aligned porosity. Freeze-casting was used to produce cryogels with longitudinally aligned pores, while cryogels with randomly distributed porosity were used as the control. The cryogels exhibited remarkable injectability and shape-recovery properties, essential for minimally invasive applications. Different tendencies in proliferation and differentiation were evident between aligned and random cryogels, underscoring the significance of the scaffold's microstructure in directing the behaviour of neural stem cells (NSC). Remarkably, aligned cryogels facilitated extensive cellular infiltration and migration, contrasting with NSC cultured on isotropic cryogels, which predominantly remained on the scaffold's surface throughout the proliferation experiment. Significantly, the proliferation assay demonstrated that on day 7, the aligned cryogels contained eight times more cells compared to the random cryogels. Consistent with the proliferation experiments, NSC exhibited the ability to differentiate into neurons within the aligned scaffolds and extend neurites longitudinally. In addition, differentiation assays showed a four-fold increase in the expression of neural markers in the cross-sections of the aligned cryogels. Conversely, the random cryogels exhibited minimal presence of cell bodies and extensions. The presence of synaptic vesicles on the anisotropic cryogels indicates the formation of functional synaptic connections, emphasizing the importance of the scaffold's microstructure in guiding neuronal reconnection.
Asunto(s)
Amnios , Diferenciación Celular , Proliferación Celular , Criogeles , Regeneración Nerviosa , Células-Madre Neurales , Andamios del Tejido , Amnios/química , Criogeles/química , Humanos , Células-Madre Neurales/citología , Andamios del Tejido/química , Animales , Porosidad , Ingeniería de Tejidos , Células CultivadasRESUMEN
Motivated by sustainability and environmental protection, great efforts have been paid towards water purification and attaining complete decolorization and detoxification of polluted water effluent. Textile effluent, the main participant in water pollution, is a complicated mixture of toxic pollutants which seriously impact human health and the entire ecosystem. Developing effective materials for potential removal of the water contaminants is urgent. Recently, cryogels have been applied in wastewater sectors due to their unique physiochemical attributes(e.g. high surface area, lightweight, porosity, swelling-deswelling, and high permeability). These features robustly affected the cryogel's performance, as adsorbent material, particularly in wastewater sectors. This review serves as a detailed reference to the cryogels derived from biopolymers and applied as adsorbents for the purification of textile drainage. We displayed an overview of: the existing contaminants in textile effluents (dyes and heavy metals), their sources, and toxicity; advantages and disadvantages of the most common treatment techniques (biodegradation, advanced chemical oxidation, membrane filtration, coagulation/flocculation, adsorption). A simple background about cryogels (definition, cryogelation technique, significant features as adsorbents, and the adsorption mechanisms) is also discussed. Finally, the bio-based cryogels dependent on biopolymers such as chitosan, xanthan, cellulose, PVA, and PVP, are fully discussed with evaluating their maximum adsorption capacity.
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Criogeles , Textiles , Aguas Residuales , Contaminantes Químicos del Agua , Purificación del Agua , Criogeles/química , Aguas Residuales/química , Biopolímeros/química , Purificación del Agua/métodos , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Liofilización , Biodegradación AmbientalRESUMEN
Cryogel-templated oleogels (CTO) were fabricated via a facile polyphenol crosslinking strategy, where apple polyphenol was utilized to crosslink the gelatin/egg white protein conjugates without forming hydrogels. After freeze-drying, cryogel templates were obtained and used to construct CTO by oil absorption. Apple polyphenol crosslinking improved the emulsion-related properties with appearance changes on samples, and infrared spectroscopy further confirmed the interactions between proteins and apple polyphenol. The crosslinked cryogels presented porous microstructures (porosity of over 96 %), enhanced thermal/mechanical stabilities, and could absorb a high content of oil (14.41 g/g) with a considerable oil holding capacity (90.98 %). Apple polyphenol crosslinking also influenced the rheological performances of CTO, where the highly crosslinked samples owned the best thixotropic recovery of 85.88 %. Moreover, after the rapid oxidation of oleogels, the generation of oxidation products was effectively inhibited by crosslinking (POV: 0.48 nmol/g, and TBARS: 0.53 mg/L). The polyphenol crosslinking strategy successfully involved egg white protein and gelatin to fabricate CTO with desired physical/chemical properties. Apple polyphenol acted as both a crosslinker and an antioxidant, which provided a good reference for fabricating pure protein-based CTO.
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Criogeles , Proteínas del Huevo , Gelatina , Malus , Compuestos Orgánicos , Oxidación-Reducción , Polifenoles , Polifenoles/química , Gelatina/química , Malus/química , Criogeles/química , Compuestos Orgánicos/química , Proteínas del Huevo/química , Reactivos de Enlaces Cruzados/química , Reología , Antioxidantes/químicaRESUMEN
The entangled assembly of bacterial cellulose (BC) nanofibers does not provide a three-dimensional (3D) macroporous structure for cellular infiltration thus hindering its use as a scaffold for bone tissue engineering. In addition, it is difficult to achieve uniform dispersion of bioactive agents in entangled BC nanofibers. To address this, the BC nanofibers were integrated with MXene, a two-dimensional nanomaterial known for its electrical signaling and mechanical strength, along with sodium alginate to form cryogel. The cryogel was fabricated using a cross-linking to enhance its mechanical properties, pores for cellular infilteration. MXene incorporation not only increased water absorption (852%-1446%) and retention (692%-973%) ability but also significantly improved the compressive stress (0.85 MPa-1.43 MPa) and modulus (0.22 MPa-1.17 MPa) confirming successful MXene reinforcement in cryogel. Biological evaluation revealed that the optimum concentration of MXene increased the cell proliferation and the osteogenic role of fabricated scaffolds was also confirmed through osteogenic gene expressions. The macropores in reconstructed MXene-BC-based cryogel provided ample space for cellular proliferation. The osteogenic role of the scaffold was examined through various gene expressions. The Quantitative polymerase chain reaction revealed that MXene-loaded scaffolds especially in low concentration, had an obvious osteogenic effect hence concluding that BC can not only be reconstructed into the desired form but osteogenic property can be induced. These findings can open a new way of reconstructing BC into a more optimal structure to overcome its structural limitations and retain its natural bioactivities.
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Alginatos , Huesos , Proliferación Celular , Celulosa , Fuerza Compresiva , Criogeles , Osteogénesis , Ingeniería de Tejidos , Andamios del Tejido , Ingeniería de Tejidos/métodos , Alginatos/química , Criogeles/química , Celulosa/química , Andamios del Tejido/química , Porosidad , Nanofibras/química , Ensayo de Materiales , Reactivos de Enlaces Cruzados/química , Materiales Biocompatibles/química , Estrés Mecánico , Humanos , AnimalesRESUMEN
The lack of practical platforms for bacterial separation remains a hindrance to the detection of bacteria in complex samples. Herein, a composite cryogel was synthesized by using clickable building blocks and boronic acid for bacterial separation. Macroporous cryogels were synthesized by cryo-gelation polymerization using 2-hydroxyethyl methacrylate and allyl glycidyl ether. The interconnected macroporous architecture enabled high interfering substance tolerance. Nanohybrid nanoparticles were prepared via surface-initiated atom transfer radical polymerization and immobilized onto cryogel by click reaction. Alkyne-tagged boronic acid was conjugated to the composite for specific bacteria binding. The physical and chemical characteristics of the composite cryogel were analyzed systematically. Benefitting from the synergistic, multiple binding sites provided by the silica-assisted polymer, the composite cryogel exhibited excellent affinity toward S. aureus and Salmonella spp. with capacities of 91.6 × 107 CFU/g and 241.3 × 107 CFU/g in 0.01 M PBS (pH 8.0), respectively. Bacterial binding can be tuned by variations in pH and temperature and the addition of monosaccharides. The composite was employed to separate S. aureus and Salmonella spp. from spiked tap water, 40% cow milk, and sea cucumber enzymatic hydrolysate, which resulted in high bacteria separation and demonstrated remarkable potential in bacteria separation from food samples.
Asunto(s)
Química Clic , Criogeles , Salmonella , Staphylococcus aureus , Criogeles/química , Staphylococcus aureus/aislamiento & purificación , Animales , Salmonella/aislamiento & purificación , Porosidad , Leche/microbiología , Leche/química , Ácidos Borónicos/química , Bovinos , Metacrilatos/químicaRESUMEN
The present study reports on the valorisation of starch waste biomass to produce dual-active cryogels and hydrogels able to adsorb water and deliver antimicrobial substances for fresh food packaging applications. Starch hydrogels were prepared by oxidation with sodium metaperiodate in water and mild conditions, while cryogels were obtained by freeze-drying process. To explore the role of starch composition on the final properties of materials, two starches differing in amylose/amylopectin ratio, were evaluated. The prepared materials were microstructurally and morphologically characterized by FTIR and NMR spectroscopy (1D, 2D, and DOSY experiments), and SEM microscopy. To provide the materials with active properties, they were loaded with antimicrobial molecules by absorption, or by crosslinking via Schiff-base reaction. All materials demonstrated high water absorption capacity and ability to deliver volatile molecules, including diacetyl and complex mixtures like mint essential oil. The release profiles of the adsorbed molecules were determined through quantitative NMR spectroscopy over time. The antibacterial activity was successfully demonstrated against Gram-positive bacterial strains for unloaded cryogels and hydrogels, and after loading with diacetyl and essential oil. The developed materials can be regarded as part of active pads for food packaging applications capable to control moisture inside the package and inhibit microbial contamination.
Asunto(s)
Antibacterianos , Criogeles , Embalaje de Alimentos , Hidrogeles , Almidón , Embalaje de Alimentos/métodos , Criogeles/química , Hidrogeles/química , Hidrogeles/farmacología , Almidón/química , Antibacterianos/farmacología , Antibacterianos/química , Pruebas de Sensibilidad Microbiana , Bacterias Grampositivas/efectos de los fármacos , Agua/químicaRESUMEN
Tissue engineering aims to improve or restore damaged tissues by using scaffolds, cells and bioactive agents. In tissue engineering, one of the most important concepts is the scaffold because it has a key role in keeping up and promoting the growth of the cells. It is also desirable to be able to load these scaffolds with drugs that induce tissue regeneration/formation. Based on this, in our study, gelatin cryogel scaffolds were developed for potential bone tissue engineering applications and simvastatin loading and release studies were performed. Simvastatin is lipoliphic in nature and this form is called inactive simvastatin (SV). It is modified to be in hydrophilic form and converted to the active form (SVA). For our study's drug loading and release process, simvastatin was used in both inactive and active forms. The blank cryogels and drug-loaded cryogels were prepared at different glutaraldehyde concentrations (1, 2, and 3%). The effect of the crosslinking agent and the amount of drug loaded were discussed with morphological and physicochemical analysis. As the glutaraldehyde concentration increased gradually, the pores size of the cryogels decreased and the swelling ratio decreased. For the release profile of simvastatin in both forms, we can say that it depended on the form (lipophilic and hydrophilic) of the loaded simvastatin.
Asunto(s)
Huesos , Criogeles , Gelatina , Simvastatina , Ingeniería de Tejidos , Andamios del Tejido , Simvastatina/química , Simvastatina/farmacología , Ingeniería de Tejidos/métodos , Gelatina/química , Criogeles/química , Andamios del Tejido/química , Porosidad , Ensayo de Materiales , Regeneración Ósea/efectos de los fármacos , Materiales Biocompatibles/química , Humanos , Reactivos de Enlaces Cruzados/químicaRESUMEN
Iodine (I2) as a broad-spectrum antiseptic has been widely used for treating bacterial infections. However, I2 has low water-solubility and sublimes under ambient conditions, which limits its practical antibacterial applications. The highly specific and sensitive reaction between I2 and starch discovered 200 years ago has been extensively applied in analytical chemistry, but the antibacterial activity of the I2-starch complex is rarely investigated. Herein, we develop a novel type of iodine-based antiseptics, iodine-soluble starch (I2-SS) cryogel, which can dissolve in water instantly and almost completely kill bacteria in 10 min at 2 µg/mL of I2. Although KI3 and the commercially available povidoneiodine (I2-PVP) solutions show similar antibacterial efficacy, the high affinity of I2 to SS largely enhances the shelf stability of the I2-SS solution with â¼73 % I2 left after one-week storage at room temperature. In sharp contrast, â¼8.5 % and â¼2.5 % I2 are detected in KI3 and I2-PVP solutions, respectively. Mechanistic study reveals that the potent antibacterial effect of I2-SS originates from its attack on multiple bacterial targets. The outstanding antibacterial activity, capability of accelerating wound healing, and good biocompatibility of I2-SS are verified through further in vivo experiments. This work may promote the development of next-generation iodine-based antiseptics for clinical use.
Asunto(s)
Antibacterianos , Antiinfecciosos Locales , Criogeles , Yodo , Solubilidad , Almidón , Agua , Yodo/química , Yodo/farmacología , Almidón/química , Almidón/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antiinfecciosos Locales/farmacología , Antiinfecciosos Locales/química , Agua/química , Criogeles/química , Animales , Staphylococcus aureus/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana , Povidona Yodada/química , Povidona Yodada/farmacología , Escherichia coli/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacosRESUMEN
Mucilage is a natural source of polysaccharides that has recently attracted attention for use in biomaterial production. It attracts attention with its easy and fast extraction, biocompatibility, high water retention capacity, and biodegradability. Although there are studies on the characterization of mucilage obtained from different plant sources, the interaction of this polymer with other polymers and its potential to form new biomaterials have not yet been sufficiently investigated. Based on this, in this study, the potential of mucilage extracted from flaxseed for the production of cryogels for tissue engineering applications was demonstrated. Firstly, yield, basic physicochemical properties, morphology, and surface charge-dependent isoelectric point determination studies were carried out for the characterization of the extracted mucilage. The successful preparation of mucilage was evaluated for the construction of cryo-scaffolds and 3D, spongy, and porous structures were obtained in the presence of chitosan and polyvinyl alcohol polymers. A heterogeneous morphology with interconnected macro and micro porosity in the range of approximately 85-115 m pore diameter was exhibited. Due to the high hydrophilic structure of the mucilage, which is attached to the structure with weak hydrogen bonds, the contact angle values of the scaffolds were obtained below 80° and they showed the ability to absorb 1000 times their dry weight in approximately 30 min. As a preliminary optimization study for the evaluation of mucilage in cryogel formation, this work introduced a new construct to be developed as wound dressing scaffold for deep and chronic wounds.