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1.
Braz. j. biol ; 84: e254010, 2024. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1345561

RESUMO

Abstract The impact of fish oil concentration on the oxidative stability of microcapsules through the spray drying process using chitosan and maltodextrin as wall material was studied. Emulsions were prepared with different Tuna fish oil (TFO) content (TFO-10%, TFO20%, TF030% TF0-40%) while wall material concentration was kept constant. Microencapsulated powder resulting from emulsion prepared with high fish oil load have high moisture content, wettability, total oil and low encapsulation efficiency, hygroscopicity and bulk tapped density. Oxidative stability was evaluated periodically by placing microcapsules at room temperature. Microcapsules prepared with TFO-10% presented high oxidative stability in terms of peroxide value (2.94±0.04) and anisidine value (1.54±0.02) after 30 days of storage. It was concluded that optimal amounts of fish oil for microencapsulation are 10% and 20% using chitosan and maltodextrin that extended its shelf life during study period.


Resumo Foi estudado o impacto da concentração de óleo de peixe na estabilidade oxidativa de microcápsulas por meio do processo de secagem por atomização, utilizando quitosana e maltodextrina como material de parede. As emulsões foram preparadas com diferentes teores de óleo de atum (TFO) (TFO-10%, TFO20%, TF030% TF0-40%), enquanto a concentração de material de parede foi mantida constante. O pó microencapsulado resultante da emulsão preparada com alta carga de óleo de peixe tem alto teor de umidade, molhabilidade e óleo total e baixa eficiência de encapsulação, higroscopicidade e densidade extraída a granel. A estabilidade oxidativa foi avaliada periodicamente colocando microcápsulas à temperatura ambiente. As microcápsulas preparadas com TFO-10% apresentaram alta estabilidade oxidativa em termos de valor de peróxido (2,94 ± 0,04) e valor de anisidina (1,54 ± 0,02) após 30 dias de armazenamento. Concluiu-se que as quantidades ideais de óleo de peixe para microencapsulação são de 10% e 20% usando quitosana e maltodextrina que prolongaram sua vida útil durante o período de estudo.


Assuntos
Animais , Óleos de Peixe , Quitosana , Pós , Atum , Estresse Oxidativo
2.
AAPS PharmSciTech ; 23(5): 163, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35680728

RESUMO

In recent years, the oral administration of vinorelbine has gradually replaced intravenous administration in the treatment of several types of tumors. Even though the risk of phlebitis is avoided with oral administration, oral vinorelbine is still not a highly patient-compliant route due to the severe gastrointestinal toxicity. Vinorelbine-loaded liposomes with high encapsulation efficiency and suitable particle size were prepared using the ammonium sulfate gradient method. Chitosan-coated liposomes showed the slowest in vitro release compared to uncoated liposomes and vinorelbine solution. No damage was observed in the intestinal epithelial cells of mice orally administered with coated vinorelbine liposomes due to the low presence of the free drug in the gastrointestinal tract and the LD50 was increased from 129.83 to 182.25 mg/kg compared to oral vinorelbine solution. In addition, the positive surface potential of chitosan-coating endowed liposomes with mucosal adhesive function, delaying the time to reach the peak plasma concentration of vinorelbine from 1 to 4 h after administration. And bioavailability was increased to 2.1-fold compared to vinorelbine solution. In short, a new strategy to address the severe gastrointestinal side effects of oral vinorelbine has been developed.


Assuntos
Quitosana , Lipossomos , Administração Oral , Animais , Disponibilidade Biológica , Camundongos , Vinorelbina
3.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 30(3): 870-876, 2022 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-35680820

RESUMO

OBJECTIVE: A dynamic gel loaded with lyophilized platelet-rich plasma-chitosan/difunctionalized polyethylene glycol (LPRP-CP) was prepared to investigate its hemostatic antibacterial and promoting wound healing of scald wounds through in vitro and in vivo experiments. METHODS: In this study, normal gauze/blank tablet (Ctrl), LPRP-CP, Chitosan HUCHUANG Powder(Chito P)and ChitoGauze XP PRO group (Chito G group) were set. The hemostatic effect and promoting healing effect of the four groups of materials were evaluated by establishing rabbit ear artery hemorrhage model and superficial Ⅱ° scalded model of skin on the back. The hemostatic time and bleeding amount were calculated and the gross and histological results of scald healing were observed. The antibacterial effect of the four groups of materials was evaluated by antibacterial test in vitro. RESULTS: In the rabbit ear arterial hemorrhage model, the hemostasis of all materials was successful. The hemostatic time of Ctrl, Chito P, LPRP-CP and Chito G groups was 213.33±38.30, 118.33±24.01, 115.00±8.37 and 111.67±11.69 s, respectively. The blood loss was 1233.83±992.27, 346.67±176.00, 193.33±121.47 and 147.50±80.66 mg, respectively. Compared with Ctrl, the hemostasis time of LPRP-CP, Chito P and Chito G group was significantly shorter (P<0.001), and the amount of blood loss of LPRP-CP and Chito G group was decreased (P<0.05). Compared with LPRP-CP, there were no significant differences in hemostatic time and blood loss between Chito P and Chito G group (P>0.05). In the model of superficial Ⅱ° scalded on the back of rabbit, the wound healing rate of LPRP-CP was faster than that of the other three groups at the same time, and the healing effect was perfect. In the antibacterial test in vitro, only LPRP-CP had better anti-S. aureus effect, and all groups had no anti-E. coli effect. CONCLUSION: LPRP-CP is an excellent hemostatic material for superficial wounds, and has certain antibacterial and wound healing effects, which has a wide academic value and research prospects.


Assuntos
Quitosana , Hemostáticos , Plasma Rico em Plaquetas , Animais , Antibacterianos/farmacologia , Quitosana/farmacologia , Hemorragia , Hemostasia , Humanos , Coelhos
4.
Int J Mol Sci ; 23(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35682630

RESUMO

The cross-linking temperature of polymers may affect the surface characteristics and molecular arrangement, which are responsible for their mechanical and physico-chemical properties. The aim of this research was to determine and explain in detail the mechanism of unit interlinkage of two-component chitosan/1,3-ß-d-glucan matrices gelled at 90 °C. This required identifying functional groups interacting with each other and assessing surface topography providing material chemical composition. For this purpose, various spectroscopic and microscopic approaches, such as attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), were applied. The results indicate the involvement mainly of the C-C and C-H groups and C=O⋯HN moieties in the process of biomaterial polymerization. Strong chemical interactions and ionocovalent bonds between the N-glucosamine moieties of chitosan and 1,3-ß-d-glucan units were demonstrated, which was also reflected in the uniform surface of the sample without segregation. These unique properties, hybrid character and proper cell response may imply the potential application of studied biomaterial as biocompatible scaffolds used in regenerative medicine, especially in bone restoration and/or wound healing.


Assuntos
Quitosana , Materiais Biocompatíveis/química , Quitosana/química , Glucanos , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Propriedades de Superfície
5.
Int J Mol Sci ; 23(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35682636

RESUMO

This study describes functional properties of bionanocomposites consisting of starch/chitosan/graphene oxide (GO) obtained using the green synthesis method, such as water-barrier and optical properties, as well as the rate of degradation by enzymatic and acid hydrolysis. The toxicity of the composites and their effects on the development of pathogenic microflora during storage of meat food products was also investigated. Although the results showed that the barrier properties of the composites were weak, they were similar to those of biological systems. The studies carried out confirmed the good optical properties of the composites containing chitosan, which makes it possible to use them as active elements of packaging. The susceptibility of starch and chitosan films to enzymatic and acid hydrolyses indicates their relatively high biodegradability. The lack of toxicity and the high barrier against many microorganisms offer great potential for applications in the food industry.


Assuntos
Quitosana , Grafite , Embalagem de Alimentos , Polímeros , Amido
6.
Methods Mol Biol ; 2487: 163-175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35687235

RESUMO

3D printing is lately utilized in biological sciences under the scope to develop customized scaffolds that will host biomolecules, either whole cells or parts of them, like enzymes. In the present work, we present a protocol to modify the surface of 3D printed polylactic acid (PLA) well-plates with the aim to co-immobilize multiple enzymes that will perform cascade reactions. Detailed steps to design and print the final models are described. The developed protocol for surface modification is based on coating with chitosan biopolymer and covalent immobilization of the enzymes ß-glucosidase, glucose oxidase, and peroxidase via glutaraldehyde cross-linking. Enzymatic activity measurements indicative of the catalytic performance of the system are also presented.


Assuntos
Quitosana , Poliésteres , Enzimas Imobilizadas , Impressão Tridimensional
7.
PLoS One ; 17(6): e0269153, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35687548

RESUMO

Nontypeable Haemophilus influenzae (NTHi) is a common opportunistic pathogen that colonizes the nasopharynx. NTHi infections result in enormous global morbidity in two clinical settings: otitis media in children and acute exacerbation of chronic obstructive pulmonary disease (COPD) in adults. Thus, there is an urgent need to design and develop effective vaccines to prevent morbidity and reduce antibiotic use. The NTHi outer membrane protein P6, a potential vaccine candidate, is highly conserved and effectively induces protective immunity. Here, to enhance mucosal immune responses, P6-loaded mannose-modified chitosan (MC) microspheres (P6-MCMs) were developed for mucosal delivery. MC (18.75%) was synthesized by the reductive amination reaction method using sodium cyanoborohydride (NaBH3CN), and P6-MCMs with an average size of 590.4±16.2 nm were successfully prepared via the tripolyphosphate (TPP) ionotropic gelation process. After intranasal immunization with P6-MCMs, evaluation of humoral immune responses indicated that P6-MCMs enhance both systemic and mucosal immune responses. Evaluation of cellular immune responses indicated that P6-MCMs enhance cellular immunity and trigger a mixed Th1/Th2-type immune response. Importantly, P6-MCMs also trigger a Th17-type immune response. They are effective in promoting lymphocyte proliferation and differentiation without toxicity in vitro. The results also demonstrate that P6-MCMs can effectively induce MHC class I- and II-restricted cross-presentation, promoting CD4+-mediated Th immune responses and CD8+-mediated cytotoxic T lymphocyte (CTL) immune responses. Evaluation of protective immunity indicated that immunization with P6-MCMs can reduce inflammation in the nasal mucosa and the lung and prevent NTHi infection. In conclusion, MCMs are a promising adjuvant-delivery system for vaccines against NTHi.


Assuntos
Quitosana , Infecções por Haemophilus , Vacinas Anti-Haemophilus , Animais , Anticorpos Antibacterianos , Proteínas da Membrana Bacteriana Externa , Infecções por Haemophilus/prevenção & controle , Haemophilus influenzae , Imunidade nas Mucosas , Manose , Camundongos , Camundongos Endogâmicos BALB C , Microesferas , Mucosa Nasal
8.
Sci Rep ; 12(1): 9627, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35688889

RESUMO

The effects of the particle fraction in toothpastes in the context of erosion and erosive tooth wear has not been fully elucidated. Thus, aim of this study was to investigate experimental toothpastes, each with one specific particle type. Toothpastes with seven different types of silica or alumina were prepared as slurry either with or without active ingredients (NaF or F/Sn). Human enamel samples were exposed to a cyclic erosion/abrasion model, and were either treated with the respective slurries only or additionally brushed in a brushing machine. Tissue loss was profilometrically monitored. After treatment with slurries without active ingredients or with NaF, tissue loss increased significantly within groups over time (p < 0.001 each). At the end of the trial, there were minor differences between groups (not exceeding 10-20%; p > 0.05 for most comparisons). After treatment with the F/Sn slurries, tissue loss stagnated completely over time, with the exception of one silica type and alumina, but both still reduced tissue loss by 40-50% (compared to control p < 0.001 each). Relative to the type of the active ingredient, the particle type seems to be a secondary factor for the efficacy of toothpastes on erosion and erosive tooth wear in enamel.


Assuntos
Quitosana , Abrasão Dentária , Erosão Dentária , Desgaste dos Dentes , Óxido de Alumínio , Quitosana/farmacologia , Esmalte Dentário , Humanos , Dióxido de Silício , Fluoreto de Sódio/farmacologia , Erosão Dentária/prevenção & controle , Escovação Dentária , Cremes Dentais/farmacologia
9.
Food Res Int ; 156: 111355, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35650981

RESUMO

In this study, carboxymethyl chitosan (CMCS) and N-acetylneuraminic acid (NeuAc) were used to develop C-NeuAc hydrogels to encapsulate Pediococcus pentosaceus QK-1. The mechanical properties, thermal stability, in vitro degradation, and pH sensitivity of the hydrogel were evaluated. The C-NeuAc concentration required for optimal hydrogel performance was 3% (w/v). Hydrogel swelling behaviour was effectively assessed by Fickian diffusion and Schott's second-order kinetic models. The hydrogel demonstrated excellent biocompatibility and low in vitro cytotoxicity. An in vitro assay revealed that the viability of Pediococcus pentosaceus QK-1 in C-NeuAc had decreased by only 1.41 log (CFU/ mL) after exposure to simulated acidic gastric fluid. Moreover, the survival rate of the encapsulated and free Pediococcus pentosaceus QK-1 cells were 80.1% and virtually zero, respectively, after passage through the gastrointestinal tract. It was empirically determined that low temperature and freeze-drying were the ideal condition and method to ensure storage longevity of the hydrogel-encapsulated probiotic. Hence, C-NeuAc hydrogel is highly desirable as a food-grade probiotic delivery vehicle.


Assuntos
Quitosana , Hidrogéis , Quitosana/química , Hidrogéis/química , Concentração de Íons de Hidrogênio , Ácido N-Acetilneuramínico , Pediococcus pentosaceus
10.
Food Res Int ; 156: 111309, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35651068

RESUMO

The development of cholesterol-free mayonnaise has attracted increasing interest in the food colloid field, due to the potential health concerns as a result of consumption of cholesterol-rich mayonnaise. One effective strategy in this regard is to substitute or partially substitute egg yolk with other organic emulsifiers and stabilizers, without affecting the quality of the product. In the work, we reported an effective strategy to fabricate high freeze-thaw-stability high internal phase emulsions (HIPEs), using complexes of a heated soy protein isolate (SPI) and chitosan (CS) at pH 3.0 as the emulsifiers and stabilizers. The SPI/CS complexes, formed even at a very low CS-to-SPI ratio, e.g., 1:10, showed a high capacity to stabilize HIPEs with a high freeze-thaw stability. Increasing the CS-to-SPI ratio in the complexes resulted in a progressive strengthening of gel network in the corresponding HIPEs, together with a gradual improvement of emulsification performance. The gel network of the HIPEs stabilized by the SPI/CS complexes was mainly maintained by the inter-droplet noncovalent interactions involving the CS molecules. The presence of CS also progressively increased the percentage of adsorbed proteins at the interface, and decreased the surface coverage of proteins at the interface. The high freeze-thaw stability of such HIPEs might be unrelated to the ice crystal formation during the freezing, and was more likely associated with the strong steric repulsion contributed to the adsorbed CS molecules between different droplets. The results indicated that the complexation of heated SPI and CS could provide an effective strategy to facilely fabricate outstanding freeze-thaw-stability HI PEs as potential mayonnaise replacers.


Assuntos
Quitosana , Proteínas de Soja , Emulsificantes , Emulsões/química , Congelamento , Concentração de Íons de Hidrogênio , Cetonas , Proteínas de Soja/química
11.
Ultrason Sonochem ; 87: 106052, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35660275

RESUMO

In this study, chitosan(CS), nano-silicon aerogels(nSA) and tea polyphenols(TP) were used as film-forming materials and processed with ultrasonication to form films using the tape-casting method. The effects of ultrasonication time, temperature and frequency on the properties of CS/nSA/TP film were explored via material property testing. The results of response surface showed that the maximum tensile strength of the film was 4.036 MPa at ultrasonication time(57.97 min), temperature(37.26 °C) and frequency(30 kHz). The maximum elongation at break of the film was 279.42 % at ultrasonication time(60.88 min), temperature(39.93 °C) and frequency(30 kHz). Due to cavitation and super-mixing effects, ultrasonication may make the surface of the film smoother and easier to degrade. After ultrasonication, TPs were protected by the 3D network structure composed of CS and nSA. Ultrasonication improved the antioxidant and antibacterial properties of the film. These results show that ultrasonication is an effective method to improve the properties of films.


Assuntos
Quitosana , Quitosana/química , Embalagem de Alimentos/métodos , Polifenóis/química , Dióxido de Silício , Chá , Resistência à Tração
12.
Carbohydr Polym ; 292: 119617, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725152

RESUMO

Environmentally friendly coatings of chitosan-derivatives with natural aldehydes were investigated for corrosion protection of magnesium AZ31 alloy. The derivatives were characterized using FTIR and UV-Vis, and the swelling degree of their films was determined in 3.5 wt% NaCl solution. The coated samples were characterized using scanning electron microscopy, potentiodynamic polarization and electrochemical impedance spectroscopy. The results indicated that, as the modification degree increases, the corrosion current density and the swelling degree decrease, whereas the impedance modulus increases. For the first time it was proposed relations between |Z| and swelling with the modification degree.


Assuntos
Quitosana , Magnésio , Ligas/química , Materiais Revestidos Biocompatíveis/química , Corrosão , Impedância Elétrica , Magnésio/química
13.
Carbohydr Polym ; 292: 119642, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725155

RESUMO

Interaction of binary chitosan/nonionic surfactant (NIS) system with sodium dodecyl sulfate (SDS) in aqueous solution is described using turbodimetry, light scattering, electophoretic mobility and cryogenic electron microscopy. The formation of insoluble CHI/SDS complexes is weakened with a decrease in molecular weight of chitosan and critical micelle concentration of NIS as well as with an increase in NIS concentration. Soluble chitosan/NIS complexes absorb SDS molecules until the charge of mixed chitosan/NIS/SDS complexes reaches a critical value that depends on chitosan molecular weight followed by aggregation of primary electrostatic complexes via hydrogen bonding to complex nanoparticles. In contrast to formation of asymmetric swarm-like structures in the binary chitosan/SDS system, the aggregation of complex nanoparticles in the ternary chitosan/NIS/SDS system occurs by a head-to-tail binding mechanism with formation of elongated filamentous microstructures. The finding can be promising for preparation of microbiologically stable pharmaceutical and cosmetic compositions and drug delivery systems containing mixed surfactants.


Assuntos
Quitosana , Quitosana/química , Micelas , Dodecilsulfato de Sódio/química , Tensoativos/química
14.
Carbohydr Polym ; 292: 119643, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725156

RESUMO

Bacterial infection and oxidative stress seriously delay wound healing. Here, magnolol-grafted-chitosan hydrochloride (CSCl-MAG) was synthesized and crosslinked with genipin to form hydrogel (CSMH). By embedding magnolol-loaded chitosan nanocapsules (MCNGs) into CSMH, we designed a novel nanocapsule- embedded hydrogel dressing (MCNG-H) with sustained antibacterial and antioxidant properties. The swelling, rheology, cytotoxicity, antibacterial and antioxidant properties of MCNG-H were studied. MCNG-H exhibited good swelling properties and biocompatibility. The antibacterial and antioxidant assays in vitro demonstrated the corporative effect of CSM-H and MCNGs in inhibiting bacteria and eliminating reactive oxygen species (ROS). Moreover, MCNG-H revealed the pH-responsive release profiles of loaded MAG, and ensured sustained release of MAG with the dual protective effects of MCNG and CSMH, which helped to maintain long-term antibacterial and antioxidant activities. Finally, MCNG-H significantly accelerated wound healing in a splinted excisional dermal wound model, promising a competitive dressing for the treatment of infected wounds.


Assuntos
Quitosana , Nanocápsulas , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Compostos de Bifenilo , Quitosana/farmacologia , Hidrogéis/farmacologia , Concentração de Íons de Hidrogênio , Lignanas , Cicatrização
15.
Carbohydr Polym ; 292: 119648, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725158

RESUMO

To better mimic the structure of skin tissue, the use of a multi-layered wound dressing has been proposed. In the present study, a sponge-nanofibrous bi-layer dressing is designed. For this purpose, a chitosan/polyethylene glycol (CsPEG) sponge with advanced platelet-rich fibrin (A-PRF) was prepared as the upper layer of wound dressing, and a Cs/L-arginine electrospun nanofiber layer as the bottom layer. After physical, chemical and mechanical evaluations, the release of platelet-derived growth factor-AB (PDGF-AB), vascular endothelial growth factor (VEGF) and L-arginine were investigated. The antibacterial activity, cell viability and attachment of Bi-layer1.5 dressing (CsPEG/1.5A-PRF sponge coated with Cs/0.5 L-arginine nanofibers) were significantly higher than other dressings. Also, Bi-layer1.5 dressing increased the angiogenic potential and accelerated the wound healing, compared to other samples. Given the promising obtained results, the use of Bi-layer1.5 wound dressing with the ability to release growth factors and L-arginine is highly recommended to treat full-thickness wounds.


Assuntos
Quitosana , Nanofibras , Fibrina Rica em Plaquetas , Antibacterianos/farmacologia , Arginina , Bandagens , Biomimética , Quitosana/química , Nanofibras/química , Fator A de Crescimento do Endotélio Vascular
16.
Carbohydr Polym ; 292: 119676, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725171

RESUMO

Molecular dynamics modeling was applied to predict chitosan molecule conformations, the contour length, the gyration radius, the effective cross-section and the density in electrolyte solutions. Using various experimental techniques the diffusion coefficient, the hydrodynamic diameter and the electrophoretic mobility of molecules were determined. This allowed to calculate the zeta potential, the electrokinetic charge and the effective ionization degree of the chitosan molecule as a function of pH and the temperature. The chitosan solution density and zero shear dynamic viscosity were also measured, which enabled to determine the intrinsic viscosity increment. The experimental results were quantitatively interpreted in terms of the slender body hydrodynamics exploiting molecule characteristics derived from the modeling. It is also confirmed that this approach can be successfully used for a proper interpretation of previous literature data obtained under various physicochemical conditions.


Assuntos
Quitosana , Hidrodinâmica , Eletrólitos/química , Simulação de Dinâmica Molecular , Soluções , Viscosidade
17.
Carbohydr Polym ; 292: 119678, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725173

RESUMO

To meet the requirement of personalization, there is an urgent need to develop a simple, efficient and versatile manufacturing method for customized contact lens manufabrication. Here, we report a novel electrofabrication methodology (i.e., electrodeposition) for the fabrication of hydrogel contact lenses, which can induce covalent cross-linking between chitosan and epichlorohydrin simultaneously. The transmittance and toughness of hydrogels are improved by electrochemical cross-linking without affecting their oxygen permeability. Furthermore, the geometry of the chitosan based hydrogel contact lenses can be customized simply by the electrode template, and its characteristics can be regulated by electrical signals and electrochemical cross-linking. The electrodeposited hydrogel contact lenses have good optical properties, mechanical properties and biocompatibility, and their anti-adhesion properties to Staphylococcus aureus are close to commercial contact lenses. This work reveals the mechanism of electrochemical cross-linking between chitosan and epichlorohydrin and provides an alternative method for contact lens fabrication.


Assuntos
Quitosana , Lentes de Contato , Quitosana/química , Galvanoplastia , Epicloroidrina , Hidrogel de Polietilenoglicol-Dimetacrilato , Hidrogéis/química
18.
Carbohydr Polym ; 292: 119687, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725178

RESUMO

In this study, a new type of biodegradable, injectable, self-healing, and low-toxic CMCSH, formed by N, O-carboxymethyl chitosan-heparin (CMCS-Hep) and carboxymethyl cellulose-aldehyde (CMC-A), was designed to deliver drug for promoting the progress of the diabetic wound healing. CMCS was modified with Hep for the first time to synthesize CMCS-Hep, and CMC-A was synthesized by the periodate oxidation method. First, SOD encapsulated in the CMCSH was applied to the diabetic wound bed to moderate the microenvironment, then rhEGF retained in the CMCSH was sustainedly released to the wound area. These results indicated that the dual-drug delivery system had the ability to improve drug availability, promote cell migration and proliferation, reduce DNA damage, shorten the inflammatory period, and accelerate the deposition of collagen fibers and the formation of blood vessels in the model with diabetic skin injury, suggesting that CMCSH as drug carriers had positive effects on diabetic wound healing.


Assuntos
Quitosana , Diabetes Mellitus , Carboximetilcelulose Sódica/farmacologia , Quitosana/farmacologia , Humanos , Hidrogéis/farmacologia , Cicatrização
19.
Carbohydr Polym ; 292: 119693, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725181

RESUMO

In the present study, extracellular matrix (ECM)-mimicking nanofibrous chitosan microspheres (NCM) were developed via thermal induction of chitosan molecular chain from alkaline/urea aqueous solution. The regeneration of NCM from chitosan was proved to be physical process. The morphology of NCM could be precisely controlled by adjusting the initial solution concentration and the reaction temperature. The NCM possessed desirable in vitro/vivo biocompatibility and biodegradability. The excellent cell adhesion capability of NCM facilitated the formation of large-sized 3D geometric constructs in vitro. The NCM promoted in vitro osteogenic differentiation of rat bone marrow stem cells (rMSCs). Finally, pre-differentiated rMSCs-NCM constructs obviously enhanced in vivo bone healing of rat calvarial defects. This work opened up a new avenue for the construction of chitosan microspheres with ECM-like nanofibrous structure, indicated the great potential of the NCM as micro-Noah's Ark for stem cells to anchor, proliferate, and pre-differentiate for tissue engineering.


Assuntos
Quitosana , Nanofibras , Animais , Regeneração Óssea , Diferenciação Celular , Quitosana/química , Matriz Extracelular/química , Microesferas , Nanofibras/química , Osteogênese , Ratos , Engenharia Tecidual , Tecidos Suporte/química
20.
Carbohydr Polym ; 292: 119725, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725193

RESUMO

In this work, chitosan chains were crosslinked with different contents of vanillin (Van), characterized and loaded with curcumin (CUR), a hydrophobic drug. Sodium dodecyl sulfate (SDS), Tween 20® (T20) and ß-cyclodextrin (ßCD) were used as curcumin carriers. Films prepared with Van 20 % yielded gel content of 70 %, swelling degree of ~23 gwater/g, bound water and capillary water, as revealed by Time-Domain Nuclear Magnetic Resonance measurements. Films prepared with higher Van contents showed small swelling degree (< 1.6 gwater/g) and hydrophobicity, making them inadequate for drug loading. UV-Vis and fluorescence spectroscopic studies indicated that Van 20 % combined with SDS and SDS/ßCD presented the highest CUR uptake (~3.0 mg/g), favored by electrostatic interactions and hydrophobic interactions. CHI and Van 20 % films did not present any cytotoxicity in human neuroblastoma SH-SY5Y cells. At pH 1.0 the films were completely soluble, pointing to their potential application as gastric delivery systems for hydrophobic drugs. Chemical compounds studied in the manuscript: Chitosan, vanillin, curcumin, ß-cyclodextrin, sodium dodecyl sulfate, polyethylene glycol sorbitan monolaurate.


Assuntos
Quitosana , Curcumina , Neuroblastoma , beta-Ciclodextrinas , Benzaldeídos , Quitosana/química , Curcumina/química , Curcumina/farmacologia , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Humanos , Dodecilsulfato de Sódio , Água/química , beta-Ciclodextrinas/química
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