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1.
Molecules ; 26(9)2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33923304

RESUMO

Chitosan is a non-toxic biological material, but chitosan is insoluble in water, which hinders the development and utilization of chitosan. Chitosan derivatives N-2-Hydroxypropyl trimethyl ammonium chloride (N-2-HACC) and carboxymethyl chitosan (CMCS) with good water solubility were synthesized by our laboratory. In this study, we synthesized mesoporous SiO2 nanoparticles by the emulsion, and then the mesoporous SiO2 nanoparticles were modified with γ-aminopropyltriethoxysilane to synthesize aminated mesoporous SiO2 nanoparticles; CMCS and N-2-HACC was used to cross-link the aminated mesoporous SiO2 nanoparticles to construct SiO2@CMCS-N-2-HACC nanoparticles. Because the aminated mesoporous SiO2 nanoparticles with positively charged can react with the mucous membranes, the virus enters the body mainly through mucous membranes, so Newcastle disease virus (NDV) was selected as the model drug to evaluate the performance of the SiO2@CMCS-N-2-HACC nanoparticles. We prepared the SiO2@CMCS-N-2-HACC nanoparticles loaded with inactivated NDV (NDV/SiO2@CMCS-N-2-HACC). The SiO2@CMCS-N-2-HACC nanoparticles as delivery carrier had high loading capacity, low cytotoxicity, good acid resistance and bile resistance and enteric solubility, and the structure of NDV protein encapsulated in the nano vaccine was not destroyed. In addition, the SiO2@CMCS-N-2-HACC nanoparticles could sustain slowly released NDV. Therefore, the SiO2@CMCS-N-2-HACC nanoparticles have the potential to be served as delivery vehicle for vaccine and/or drug.


Assuntos
Quitosana/farmacologia , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Doença de Newcastle/tratamento farmacológico , Animais , Proliferação de Células/efeitos dos fármacos , Quitosana/análogos & derivados , Humanos , Nanopartículas/uso terapêutico , Doença de Newcastle/patologia , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/efeitos dos fármacos , Vírus da Doença de Newcastle/patogenicidade , Dióxido de Silício/química , Vacinas/química , Vacinas/farmacologia , Água/química
2.
Int J Nanomedicine ; 16: 2897-2915, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33907399

RESUMO

Background: Surgery is considered to be a potentially curative approach for gastric cancer. However, most cases are diagnosed at a very advanced stage for the lack of typical symptoms in the initial stage, which makes it difficult to completely surgical resect of tumors. Early diagnosis and precise personalized intervention are urgent issues to be solved for improving the prognosis of gastric cancer. Herein, we developed an RGD-modified ROS-responsive multifunctional nanosystem for near-infrared (NIR) imaging and photothermal therapy (PTT) against gastric cancer. Methods: Firstly, the amphiphilic polymer was synthesized by bromination reaction and nucleophilic substitution reaction of carboxymethyl chitosan (CMCh) and 4-hydroxymethyl-pinacol phenylborate (BAPE). Then, it was used to encapsulate indocyanine green (ICG) and modified with RGD to form a smart multifunctional nanoparticle targeted to gastric cancer (CMCh-BAPE-RGD@ICG). The characteristics were determined, and the targeting capacity and biosafety were evaluated both in vitro and in vivo. Furthermore, CMCh-BAPE-RGD@ICG mediated photothermal therapy (PTT) effect was studied using gastric cancer cells (SGC7901) and SGC7901 tumor model. Results: The nanoparticle exhibited suitable size (≈ 120 nm), improved aqueous stability, ROS-responsive drug release, excellent photothermal conversion efficiency, enhanced cellular uptake, and targeting capacity to tumors. Remarkably, in vivo studies suggested that CMCh-BAPE-RGD@ICG could accurately illustrate the location and margin of the SGC7901 tumor through NIR imaging in comparison with non-targeted nanoparticles. Moreover, the antitumor activity of CMCh-BAPE-RGD@ICG-mediated PTT could effectively suppress tumor growth by inducing necrosis and apoptosis in cancer cells. Additionally, CMCh-BAPE-RGD@ICG demonstrated excellent biosafety both in vitro and in vivo. Conclusion: Overall, our study provides a biocompatible theranostic nanoparticle with enhanced tumor-targeting ability and accumulation to realize NIR image-guided PTT in gastric cancer.


Assuntos
Nanopartículas Multifuncionais/química , Nanopartículas Multifuncionais/uso terapêutico , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/terapia , Animais , Ácidos Borônicos/química , Linhagem Celular Tumoral , Quitosana/análogos & derivados , Quitosana/química , Feminino , Humanos , Verde de Indocianina/química , Verde de Indocianina/farmacocinética , Camundongos Endogâmicos BALB C , Oligopeptídeos/química , Fototerapia/métodos , Polímeros/química , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Carbohydr Polym ; 260: 117839, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712174

RESUMO

The efficacy and mode of action of biodegradable chitosan (CS) and carboxymethyl chitosan (CMCS) organic polymer nanoparticles (NPs) on insects were studied. The prepared CS/CMCS-NPs were spherical with a particle size of 142.1 ± 2.0 nm. The swelling test showed that they were pH-sensitive, and the swelling rate was 554 % at pH 4.5. It was found that CS/CMCS-NPs had insecticidal efficacy against red fire ants (S. invicta). The mortality of red fire ants on the 6th day after treatment with 0.2 % and 0.06 % CS/CMCS-NPs suspensions was 98.33 ± 1.67 % and 48.33 ± 3.33 %, respectively. After CS/CMCS-NPs treatment, the food intake, growth, and development of red fire ants were inhibited; the midgut was significantly expanded; and the activity of digestive enzymes in the midgut was decreased. Our findings suggest that CS/CMCS-NPs mainly inhibited the digestion function of the midgut, leading to the death of red fire ants.


Assuntos
Quitosana/análogos & derivados , Quitosana/química , Inseticidas/química , Nanopartículas/química , Animais , Formigas/efeitos dos fármacos , Formigas/fisiologia , Peso Corporal/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Lipase/antagonistas & inibidores , Lipase/metabolismo , Nanopartículas/toxicidade , Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo
4.
Carbohydr Polym ; 261: 117821, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766331

RESUMO

Damage to the cell membrane is an effective method to prevent drug resistance in plant fungal diseases. Here, we proposed a negative remodeling model of the cell membrane structure induced by the C-coordinated O-carboxymethyl chitosan Cu (II) complex (O-CSLn-Cu). FITC-labeled O-CSLn-Cu (FITC-O-CSLn-Cu) was first synthesized via a nucleophilic substitution reaction and confirmed by FT-IR. FITC-labeled O-CSLn-Cu could pass through the fungal cell membrane, as detected by confocal laser scanning microscopy (CLSM) coupled with fluorescein isothiocyanate (FITC)-fluorescence. O-CSLn-Cu treatment led to apparent morphological changes in the membranes of P. capsici Leonian and giant unilamellar vesicles (GUVs) by transmission electron microscopy (TEM). Then, we performed component analysis of the cell membrane from the P. capsici Leonian affected by O-CSLn-Cu with a particular interest in membrane physicochemical properties. Many unsaturated fatty acids (UFAs) and key enzymes promoting UFA synthesis of the cell membrane were downregulated. Similarly, a large number of membrane proteins responsible for substance transport and biochemical reactions were downregulated. Furthermore, O-CSLn-Cu treatments increased plasma membrane permeability with significant leakage of intercellular electrolytes, soluble proteins and sugars, and lipid peroxidation with decreasing membrane fluidity. Finally, aquaporin 10 was proven to be a potential molecular target sensitive to antimicrobial agents according to composition analysis of membrane structure and immunohistochemistry.


Assuntos
Antifúngicos/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Quitosana/análogos & derivados , Cobre/química , Phytophthora/efeitos dos fármacos , Animais , Antifúngicos/síntese química , Antifúngicos/química , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Quitosana/química , Quitosana/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Cobre/farmacologia , Fungicidas Industriais/síntese química , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Fluidez de Membrana/efeitos dos fármacos , Lipídeos de Membrana/fisiologia , Phytophthora/metabolismo , Phytophthora/ultraestrutura , Coelhos , Esporos/efeitos dos fármacos , Esporos/fisiologia
5.
Carbohydr Polym ; 261: 117869, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766356

RESUMO

Osteoarthritis (OA) is an age-related joint disorder and one of the leading causes of physical disability. In this study, we designed and synthesized a new polysaccharide complex, carboxymethyl chitosan strontium (CMCS-Sr), which is believed to have positive effects on relieving OA. The synthesized CMCS-Sr was structurally verified by SEM, EDS, FTIR, etc. The therapeutic effects of CMCS-Sr were evaluated using various biological experiments. The cell viability and apoptosis results reveal that CMCS-Sr can significantly promote the proliferation and suppress OA chondrocytes apoptosis in vitro. The immunofluorescence staining results suggest that CMCS-Sr facilitates the promotion of the secretion of Type II collagen (Col-II). The transcriptomic results support the observed positive effects of CMCS-Sr on inhibiting chondrocytes apoptosis and alleviating inflammatory reactions. Moreover, animal study demonstrates that CMCS-Sr effectively reduced articular cartilage damage and subchondral bone degradation. Therefore, we propose the use of CMCS-Sr as a promising candidate for relieving OA.


Assuntos
Quitosana/análogos & derivados , Osteoartrite/tratamento farmacológico , Polímeros/síntese química , Polímeros/uso terapêutico , Estrôncio/química , Animais , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Células Cultivadas , Quitosana/síntese química , Quitosana/química , Quitosana/farmacologia , Quitosana/uso terapêutico , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Condrócitos/fisiologia , Humanos , Masculino , Osteoartrite/patologia , Polímeros/química , Polímeros/farmacologia , Cultura Primária de Células , Ratos , Estrôncio/farmacologia , Estrôncio/uso terapêutico
6.
Carbohydr Polym ; 261: 117870, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766357

RESUMO

Effective wound dressings are of great significance in preventing infections and promoting wound healing. However, most existing hydrogel dressings have an inadequacy in either mechanical performance, biological activities, or versatilities. Here we presented a double-network cross-linked polysaccharide-based hydrogel composed of collagen peptide-functionalized carboxymethyl chitosan (CS) and oxidized methacrylate sodium alginate (SA). The hydrogel possessed interconnected porous morphologies, suitable swelling ratios, excellent mechanical properties, and favorable biocompatibility. Meanwhile, the in vivo studies using a mouse full-thickness skin defect model showed that the double-network CS/SA hydrogel significantly accelerated wound healing by regulating the inflammatory process, promoting collagen deposition, and improving vascularization. Therefore, the functionalized double-network hydrogel should be a potential candidate as wound dressings.


Assuntos
Curativos Hidrocoloides , Hidrogéis , Polissacarídeos/química , Cicatrização/efeitos dos fármacos , Alginatos/síntese química , Alginatos/química , Alginatos/uso terapêutico , Animais , Células Cultivadas , Quitosana/análogos & derivados , Quitosana/síntese química , Quitosana/química , Quitosana/uso terapêutico , Colágeno/síntese química , Colágeno/química , Colágeno/farmacocinética , Colágeno/uso terapêutico , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Hidrogéis/uso terapêutico , Teste de Materiais , Camundongos , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacocinética , Fragmentos de Peptídeos/uso terapêutico , Polissacarídeos/uso terapêutico , Pele/efeitos dos fármacos , Pele/lesões , Pele/patologia
7.
Carbohydr Polym ; 261: 117878, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766365

RESUMO

Hydrogels have gained great attentions as wound dressing. Binding to the tissue and preventing wound infection were the basic requirements for an "ideal dressing". We employed l-DOPA and ε-Poly-l-lysine to modify thermo-sensitive hydroxybutyl chitosan (HBC) to obtain (l-DOPA) - (ε-Poly-l-lysine)-HBC hydrogels (eLHBC). The eLHBC exhibited an almost 1.5 fold (P < 0.01) increase in wet adhesion strength compared to HBC. Upon the introduction of ε-Poly-l-lysine, eLHBC presented inherent antimicrobial property and prevented wound infection and inflammation response. Bone marrow mesenchymal stem cells (BMSCs) encapsulated in the eLHBC (BMSCs ⊂ eLHBC) could secret cytokins and growth factors via paracrine and promote the migration of fibroblast cells. BMSCs ⊂ eLHBC enhanced the complete skin-thickness wound healing via promoting collagen deposition and inhibiting infection and inflammation in vivo with wound closure rate being above 99 % after 15 days. The bioinspired, tissue-adhesive eLHBC could serve as advanced wound dressings for facilitating tissue repair and regeneration.


Assuntos
Adesivos , Curativos Hidrocoloides , Quitosana/análogos & derivados , Células-Tronco Mesenquimais/efeitos dos fármacos , Tecidos Suporte/química , Adesivos/síntese química , Adesivos/química , Adesivos/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Bioengenharia/métodos , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Bivalves/química , Bivalves/metabolismo , Adesão Celular/efeitos dos fármacos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Células Cultivadas , Quitosana/síntese química , Quitosana/química , Quitosana/farmacologia , Matriz Extracelular/química , Matriz Extracelular/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Hidrogéis/síntese química , Hidrogéis/química , Hidrogéis/farmacologia , Masculino , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Camundongos , Testes de Sensibilidade Microbiana , Peptídeos/síntese química , Peptídeos/química , Peptídeos/farmacologia , Coelhos , Ratos , Ratos Sprague-Dawley , Temperatura , Cicatrização/efeitos dos fármacos
8.
Carbohydr Polym ; 261: 117889, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766375

RESUMO

This work was aimed to synthesize novel crosslinked carboxymethyl chitosan nanoparticles (CMCS NPs) containing metformin hydrochloride (MET) using microfluidics (MF) and evaluate their performance for diabetes therapy. The field emission-scanning electron microscopy (FE-SEM) images and dynamic light scattering (DLS) results showed that the NPs average size was 77 ± 19 nm with a narrow size distribution. They exhibited a high encapsulation efficiency (∼90 %) and the controlled drug release while crosslinking using CaCl2. Eventually, the in vivo assessments dedicated an increased body weight up to 7.94 % and a decreased blood glucose level amount of 43.58 % for MF MET-loaded CMCS NPs with respect to the free drug in diabetic rats. Also, the results of histopathological studies revealed the size of the pancreatic islets to be 2.32 µm2 and ß cells intensity to be 64 cells per islet for the diabetic rats after treating with the MF-based sample. These data were close to those obtained for the healthy rats.


Assuntos
Quitosana/análogos & derivados , Diabetes Mellitus Experimental/tratamento farmacológico , Portadores de Fármacos/síntese química , Metformina/administração & dosagem , Microfluídica/métodos , Nanopartículas , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Quitosana/síntese química , Quitosana/química , Quitosana/farmacocinética , Preparações de Ação Retardada , Diabetes Mellitus Experimental/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos , Metformina/farmacocinética , Nanopartículas/química , Nanopartículas/uso terapêutico , Tamanho da Partícula , Ratos , Ratos Wistar
9.
Carbohydr Polym ; 258: 117684, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33593557

RESUMO

To control the release of nerve growth factor (NGF) in the injured peripheral nerve, NGF-loaded chitosan/PLGA composite microspheres ionically cross-linked by tripolyphosphate (TPP/Chitosan/PLGA-NGF) were prepared. The encapsulation efficiency of NGF ranged from 83.4 ± 1.5 % to 72.1 ± 1.6 % with TPP concentrations from 1 % to 10 %. Zeta potential and FT-IR analyses together with confocal microscopy demonstrated that multiple NGF-loaded PLGA microspheres were embedded in chitosan matrix, the mean size of TPP/Chitosan/PLGA-NGF microspheres ranged from 40.2 ± 3.4 to 49.3 ± 3.1 µm. The increase of TPP concentration improved the network stability and decreased the swelling ratio, resulting in the decreased NGF release from 67.7 ± 1.2 % to 45.7 ± 0.8 % in 49 days. The sustained release of NGF could promote PC12 cells differentiation and neurite growth in vitro. Moreover, in comparison with NGF solution without microencapsulation, TPP/Chitosan/PLGA-NGF microspheres enhanced sciatic nerve regeneration and prevented gastrocnemius muscle atrophy in rats. These results demonstrate the feasibility of using TPP/Chitosan/PLGA-NGF microspheres for neural tissue repair.


Assuntos
Quitosana/análogos & derivados , Microesferas , Fator de Crescimento Neural/metabolismo , Sistema Nervoso Periférico/patologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Animais , Diferenciação Celular , Quitosana/química , Reagentes para Ligações Cruzadas/farmacologia , Sistemas de Liberação de Medicamentos , Íons , Masculino , Microscopia Confocal , Músculo Esquelético/efeitos dos fármacos , Regeneração Nervosa/efeitos dos fármacos , Neuritos/metabolismo , Neurônios/metabolismo , Células PC12 , Tamanho da Partícula , Polímeros/química , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/lesões , Nervo Isquiático/cirurgia , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
10.
Carbohydr Polym ; 257: 117631, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33541657

RESUMO

The coaxial electrospinning for producing core-shell nanofibers due to control the release profile of drug by the shell layer has been developed. N-carboxymethyl chitosan (CMC)-polyvinyl alcohol (core)/poly(ε-caprolactone) (PCL) (shell) nanofibers were produced via coaxial electrospinning. Doxorubicin (DOX) and nickel ferrite nanoparticles were incorporated into the nanofibers for controlled release of DOX against MCF-7 breast cancer. The minimum CMC/PCL fiber diameter was found to be 300 nm by optimizing of three variables including voltage to distance ratio (1.5-2.5 kV/cm), CMC concentration (4-6 wt.%) and PCL concentration (8-12 wt.%). The synthesized core-shell fibers were characterized using FTIR, XRD, SEM, and TEM analysis. The extended release and controlled release of DOX from core-shell nanofibers were achieved under physiological pH without external magnetic field (EMF) and acidic pH with EMF during 25 and 7 days, respectively. The maximum cytotoxicity of MCF-7 breast cancer cells was about 83 % using CMC/PCL/nickel ferrite 10 % nanofibers and EMF.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Quitosana/análogos & derivados , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Compostos Férricos/química , Níquel/química , Poliésteres/química , Antineoplásicos/farmacologia , Quitosana/química , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Campos Magnéticos , Nanopartículas Metálicas/química , Nanofibras/química
11.
Carbohydr Polym ; 258: 117718, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33593580

RESUMO

Herein, carboxymethyl chitosan and poly(vinylpyrrolidone) based hydrogels were synthesized by electron beam irradiation with dose variations (15 kGy, 30 kGy, and 45 kGy) for drug delivery applications. Irradiation crosslinked hydrogels were characterized for swellings in different medias, chemical, thermal, cell cytotoxicity, and drug release aspects. Swelling analysis was evaluated in distilled water, buffer, and saline solutions. Fourier transform infrared analysis revealed the establishment of physical interactions and confirmed the presence of functional groups present in the drug carriers. Scanning electron microscopy depicted the porous structure, which is responsible for swelling, drug loading, and release. Cell cytotoxicity assays indicated good cell viability on RAW 264.7 cells and anticancer activity on cancerous AGS cell lines. Cumulative drug release (%) of kanamycin in PBS at pH 7.4 was more than 90 % at 168 h. These drug carriers show promise to be developed as a sustained drug delivery system.


Assuntos
Antineoplásicos/administração & dosagem , Quitosana/análogos & derivados , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Canamicina/administração & dosagem , Povidona/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Quitosana/química , Reagentes para Ligações Cruzadas/química , Preparações de Ação Retardada , Difusão , Liberação Controlada de Fármacos , Elétrons , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Canamicina/farmacologia , Camundongos , Microscopia Eletrônica de Varredura , Porosidade , Células RAW 264.7 , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Carbohydr Polym ; 256: 117533, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483050

RESUMO

For preparing stable water-in-oil-in-water emulsion, the role of nanoparticles in stabilizing the interface is very important. In this study, chitosan hydrochloride-carboxymethyl chitosan (CHC-CMC) nanoparticles were prepared considering electrostatic interactions; then the emulsion was prepared and the stability characteristics in presence of NaCl (0-200 mmol/L) and 30 d storage were studied. CHC-CMC nanoparticles (261 nm) were obtained when the CHC: CMC ratio was 1:2. CHC-CMC formation was verified by FT-IR when a new peak appeared at 1580 cm-1; W2 contained 2 wt % CHC-CMC and W1 contained 1 wt % sodium alginate, the creaming index (81.6 %) was higher for the emulsions than Tween 80 (67.4 %) after 30 d. Confocal laser scanning microscopy confirmed the double microstructures, in contrast to the collapse with Tween 80, because the CHC-CMC nanoparticles were densely adsorbing on the oil-water interface. This indicates that CHC-CMC has a stronger ability to stabilize W1/O/W2 emulsion than Tween 80.


Assuntos
Quitosana/análogos & derivados , Quitosana/química , Emulsões , Nanopartículas/química , Alginatos/química , Íons , Microscopia , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanotecnologia/métodos , Polissorbatos/química , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Carbohydr Polym ; 256: 117579, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483073

RESUMO

This study aimed to develop an active edible film based on carboxymethyl chitosan (CMCS) and pullulan (Pul) incorporated with galangal essential oil (GEO) by the casting method. And their physical properties, structural and preservation effect on mangoes were characterized. The CMCS/Pul ratio was determined to be 2.5:2.5 after the optimization of physical properties, mechanical properties and barrier properties of the blend film. The results of FT-IR and XRD showed that hydroxyl groups of Pul interacted with the carboxyl groups of CMCS and the blend films had good compatibility. Good thermal stability of CMCS/Pul-GEO films was further proven by TGA curves. The CMCS/Pul-8 %GEO film showed effective preservations on mango fruits during 15 days of storage at 25 ± 1 °C, based on the characterization by fruits weight loss, firmness, titratable acidity, soluble solids. Consequently, CMCS/Pul-GEO blend films may be a promising eco-friendly packaging material for the industrial application of fruit preservation.


Assuntos
Alpinia/química , Quitosana/análogos & derivados , Conservação de Alimentos/métodos , Frutas , Glucanos/química , Mangifera , Óleos Voláteis/química , Antibacterianos/química , Quitosana/química , Filmes Comestíveis , Embalagem de Alimentos/métodos , Oxigênio/química , Permeabilidade , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Temperatura , Resistência à Tração , Termogravimetria , Água/química , Difração de Raios X
14.
Carbohydr Polym ; 256: 117590, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483076

RESUMO

Hydrogels, being highly biocompatible and adaptable with biological tissues, have shown great usability in biomedical applications. In this research, a novel hydrogel film developed from carboxymethyl chitosan (CMCS) loaded with waterborne polyurethane-gelatin hydrolysate was synthesized via aqueous emulsion copolymerization. The synthesized hydrogel film was characterized using mechanical strength tests, FTIR, XPS, SEM, AFM, and various other analysis technologies. The results demonstrated that the hydrogel film exhibited good thermal stability, swelling behavior, as well as controllable biodegradability. Specifically, when the CMCS content was loaded at 6 %, the maximum tensile strength and elongation at the break of the hydrogel film were reached 31.69 MPa and 447.187, respectively. The disk diffusion tests indicated that the hydrogel film presented significant antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). These results indicate that hydrogel films with high mechanical strength and high antibacterial activity could be used for wound dressing applications.


Assuntos
Bandagens , Materiais Biocompatíveis/química , Quitosana/análogos & derivados , Escherichia coli/efeitos dos fármacos , Metilgalactosídeos/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Biomassa , Líquidos Corporais/efeitos dos fármacos , Quitosana/química , Emulsões , Gelatina/química , Humanos , Hidrogéis/química , Poliuretanos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Resistência à Tração , Termogravimetria , Água/química
15.
Carbohydr Polym ; 256: 117609, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483085

RESUMO

Hydrogels are widely used in the biomedical field, due to their high similarity to native extracellular matrix (ECM). Most responsive hydrogels could only passively receive stimuli and independently change their properties. In this study, a photosensitive o-nitrobenzyl (NB) ester linker of polyethylene glycol (PEG) with maleimido (Mal) as terminal groups (PEG-NB-Mal) and a 5-methylfurfuryl (mF) grafted carboxymethyl chitosan (CMCS) derivative (CMCS-mF) were synthesized and used to prepare functional hydrogels via Diels-Alder (DA) reactions. The hydrogel exhibited programmable degradation properties after sequential exposure to UV light and acid treatments. It can maintain high integrity upon the single stimuli, the cascade acid and UV light treatments or the cascade UV light and alkaline treatments. Moreover, the hydrogel exhibited well controlled release profile of rhodamine B (RB). In summary, such CMCS-based hydrogels show great potential in biomedical applications. In addition, the usage of photo-induced cascade reaction in sequential degradation hydrogels can be extended to design other types of programmable smart materials.


Assuntos
Quitosana/análogos & derivados , Liberação Controlada de Fármacos , Hidrogéis/química , Fotoquímica/métodos , Ácidos/química , Quitosana/química , Reação de Cicloadição , Espectroscopia de Ressonância Magnética , Polietilenoglicóis/química , Polissacarídeos/química , Rodaminas/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Raios Ultravioleta
16.
ACS Appl Mater Interfaces ; 13(2): 3237-3245, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33405504

RESUMO

Cationic polymers are promising antibacterial agents because bacteria have a low propensity to develop resistance against them, but they usually have low biocompatibility because of their hydrophobic moieties. Herein, we report a new biodegradable and biocompatible chitosan-derived cationic antibacterial polymer, 2,6-diamino chitosan (2,6-DAC). 2,6-DAC shows excellent broad-spectrum antimicrobial activity with minimum inhibitory concentrations (MICs) of 8-32 µg/mL against clinically relevant and multidrug-resistant (MDR) bacteria including Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. Furthermore, 2,6-DAC shows an excellent synergistic effect with various clinically relevant antibiotics proved by decreasing the MICs of the antibiotics against MDR A. baumannii and methicillin-resistant Staphylococcus aureus to <1 µg/mL. In vivo biocompatibility of 2,6-DAC is proved by a dosage of 100 mg/kg compound via oral administration and 25 mg/kg compound via intraperitoneal injection to mice; 2,6-DAC does not cause any weight loss and any significant change in liver and kidney biomarkers or the important blood electrolytes. The combinations of 2,6-DAC together with novobiocin and rifampicin show >2.4 log10 reduction of A. baumannii in murine intraperitoneal and lung infection models. The novel chitosan derivative, 2,6-DAC, can be utilized as a biocompatible broad-spectrum cationic antimicrobial agent alone or in synergistic combination with various antibiotics.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Quitosana/análogos & derivados , Quitosana/farmacologia , Animais , Infecções Bacterianas/tratamento farmacológico , Sinergismo Farmacológico , Feminino , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana
17.
Carbohydr Polym ; 256: 117507, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483029

RESUMO

A series of vegetable oil-based waterborne polyurethane composites were prepared through construction of novel semi-interpenetrating polymers network using carboxymethyl chitosan (CA) as the secondary polymer phase. The effects of CA contents on storage stability, and particle size distribution of the composite dispersions and thermal stability, mechanical properties and surface wettability of composite films were investigated and discussed. The results showed that the composite dispersions displayed excellent storage stability and the biomass contents of resulting films were high up to 80 %. A significant increase in crosslinking density and glass transition temperature of the composite films were observed as the CA contents increased, which was attributed to the increasing hard segment of films and strong hydrogen bonding interaction between polyurethanes and CA. This work provided a simple method to tailor the performance of environmentally friendly vegetable oil-based waterborne polyurethane, which could find application in the field of coatings, adhesives, ink and so on.


Assuntos
Óleo de Rícino/química , Quitosana/análogos & derivados , Poliuretanos/química , Água/química , Quitosana/química , Estabilidade de Medicamentos , Humanos , Ligação de Hidrogênio , Teste de Materiais , Tamanho da Partícula , Transição de Fase , Resistência à Tração , Temperatura de Transição , Molhabilidade
18.
Carbohydr Polym ; 256: 117519, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483040

RESUMO

Vitreous, an essential dioptric medium for the human eyes, must be filled with artificial materials once damaged. Carboxymethyl chitosan (CMCTS) is one of the most important water-soluble chitosan derivatives with improved biocompatibility and biodegradability. In this study, oxidized hyaluronic acid (OHA) was prepared as crosslinking reagent. CMCTS and OHA were used to develop a biocompatible, self-repairing and in-situ injectable hydrogel for vitreous substitutes. Results showed the hydrogel with controllable swelling properties, high transparency, acceptable cytocompatibility on mouse fibroblast L929 and histocompatibility in vivo. Furthermore, hydrogel was injected in-situ into the vitreous cavity after vitrectomy on New Zealand Rabbits, no significant and persistent adverse effects were observed during the 90-day follow-up period. In addition, the hydrogel maintained intraocular pressure of the operated eyes and the inherent position of the retina. Collectively, this injectable, biodegradable, nontoxic hydrogel possessed enormous potential to become a vitreous substitute material.


Assuntos
Materiais Biocompatíveis/química , Quitosana/análogos & derivados , Ácido Hialurônico/química , Hidrogéis/química , Corpo Vítreo/cirurgia , Animais , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Ácido Hialurônico/farmacologia , Hidrogéis/farmacologia , Injeções Intraoculares , Pressão Intraocular/efeitos dos fármacos , Pressão Intraocular/fisiologia , Masculino , Camundongos , Coelhos , Ratos , Ratos Sprague-Dawley , Solubilidade , Resultado do Tratamento , Vitrectomia/métodos , Água/química
19.
Molecules ; 26(2)2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33467083

RESUMO

Chitosan is the only cationic polysaccharide found in nature. It has broad application prospects in biomaterials, but its application is limited due to its poor solubility in water. A novel chitosan derivative was synthesized by amidation of chitosan with 18ß-glycyrrhetinic acid and sialic acid. The chitosan derivatives were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and measurement of the zeta potential. We also investigated the solubility, cytotoxicity, and blood compatibility of chitosan derivatives. 18ß-glycyrrhetinic acid and sialic acid could be grafted onto chitosan molecular chains. The thermal stability of the synthesized chitosan derivatives was decreased and the surface was positively charged in water and phosphate-buffered saline. After chitosan had been modified by 18 ß-glycyrrhetinic acid and sialic acid, the solubility of chitosan was improved greatly in water and phosphate-buffered saline, and percent hemolysis was <5%. Novel amphiphilic chitosan derivatives could be suitable polymers for biomedical purposes.


Assuntos
Quitosana , Ácido Glicirretínico/análogos & derivados , Teste de Materiais , Ácido N-Acetilneuramínico , Linhagem Celular , Quitosana/análogos & derivados , Quitosana/síntese química , Quitosana/química , Quitosana/farmacologia , Ácido Glicirretínico/química , Ácido Glicirretínico/farmacologia , Humanos , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/farmacologia , Solubilidade
20.
Int J Biol Macromol ; 173: 203-210, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33484799

RESUMO

Nonwoven fabrics containing silver nanoparticles (AgNPs) are widely utilized to assist management of infected wounds and those at risk of infection. However, such materials have varied responses due to their chemical nature. Herein we investigated the correlation between the concentration of AgNPs taken up by nonwoven viscose material and antibacterial activity in a simulated wound fluid model against two bacterial models (i.e., Escherichia coli and Staphylococcus aureus). Thereafter, the developed nonwoven viscose containing AgNPs were independently coated with two polyacid carbohydrate polymers (i.e., carboxymethyl chitosan (CMCs), alginate (ALG)), and gelatin (GEL) protein in order to study their influence on the physical and biological attributes in vitro and in vivo. Intensive characterizations were utilized to monitor the physicochemical features of the developed nonwoven viscose. The results demonstrated that higher concentrations of AgNPs were taken up by viscose fabric whilewhile increasing AgNPs in the colloidal solution during padding process. Overall, the treated nonwoven fabric with and without polymers' coatings showed remarkable antibacterial activity against two bacterial models in vitro. As well as they achieved high and speed wound recovery in rats which was almost similar to commercial dermazin treatment. Therefore, it validates excellent nonwoven dressing clinically relevant to the wound type and condition.


Assuntos
Queimaduras Químicas/tratamento farmacológico , Infecções por Escherichia coli/tratamento farmacológico , Nanopartículas Metálicas/química , Prata/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Alginatos/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Bandagens , Queimaduras Químicas/microbiologia , Carboximetilcelulose Sódica/química , Quitosana/análogos & derivados , Quitosana/química , Preparações de Ação Retardada/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Infecções por Escherichia coli/microbiologia , Gelatina/química , Nanopartículas Metálicas/ultraestrutura , Ratos , Prata/química , Pele/efeitos dos fármacos , Pele/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Cicatrização/fisiologia
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