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1.
J Chromatogr A ; 1621: 461029, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32192704

RESUMO

The aim of the present study was to compare the enantioseparation performance of chiral stationary phases (CSPs) which were derived from chitosans of different sources and molecular weights. Therefore, chitosans of shrimp and crab shells were prepared. The viscosity-average molecular weights of the chitosans both prepared from shrimp and crab shells were 2.8 × 105 and 1.4 × 105. The chitosans were isobutyrylated yielding isopropylcarbonyl chitosans which were then derivatized with 4-methylphenyl isocyanate to provide chitosan 3,6-bis(4-methylphenylcarbamate)-2-(isobutyrylamide)s. The chitosan 3,6-bis(4-methylphenylcarbamate)-2-(isobutyrylamide)s were used as chiral selectors (CSs) with which the corresponding CSPs were prepared. With the same chiral analytes and under the same mobile phase conditions, the enantioseparation capability of the CSPs was evaluated by high-performance liquid chromatography. In two CSs prepared from the same source, the one with higher molecular weight showed better enantioseparation capability; in two CSs prepared with the chitosans of the same molecular weight, the one derived from shrimp shell exhibited better performance. With regard to the two shrimp chitosan CSs, most of chiral analytes interacted more strongly with the one with lower molecular weight, and an opposite trend was found for the two crab chitosan CSs. Based on the results observed in the present study and in previous work, we believe that the influence of molecular weight on CSP enantioseparation performance is related to the substituent introduced in the CS molecule.


Assuntos
Quitosana/química , Cromatografia Líquida de Alta Pressão , Animais , Braquiúros/química , Quitosana/análogos & derivados , Peso Molecular , Penaeidae/química , Estereoisomerismo
2.
Int J Nanomedicine ; 15: 821-837, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32103939

RESUMO

Introduction: Hepatocellular carcinoma represents a major health problem with the related death numbers still increasing. Active targeting is considered an attractive choice for the development of selective therapeutics with limited side effects and improved efficiency. In this study, we report the design, development and evaluation of a novel dual-ligand functionalized core-shell chitosan-based nanocarrier for the selective delivery of doxorubicin (DOX) for treatment of hepatocellular carcinoma (HCC). Methods: Following factorial design experiments, DOX was initially complexed with negatively charged carboxymethyl chitosan-g-poly(acrylate) and then the complex was coated with a positively charged dual-ligand (lactobionic acid and glycyrrhetinic acid)-conjugated chitosan. The developed active targeting system was then tested in vitro on Hep-G2 cells using flow cytometry and fluorescence imaging. Results: The obtained results proved the ability of the dual-ligand system to enhance the intracellular uptake of the drug by 4-fold and 8-fold after 4 hrs and 24 hrs of incubation, respectively. The efficiency of the dual-ligand functionalized nanoparticles was also tested in vivo on Wistar rats with induced liver tumors. Testing of serum biomarkers (albumin, creatinine, urea, alpha fetoprotein, ALT, AST and ALP) in addition to histopathological microscopic examination of liver, kidney and heart tissues confirmed the enhanced safety of the developed targeted nanocarrier system compared to the conventional DOX. Discussion: The developed targeted system showed improved intracellular drug delivery and uptake as well as enhanced safety profile. The nanoparticles were formed based on electrostatic interactions providing the flexibility that allows their use as a model for delivery of other drugs and other targets.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Quitosana/análogos & derivados , Portadores de Fármacos/química , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Nanopartículas/química , Animais , Carcinoma Hepatocelular/patologia , Quitosana/química , Dissacarídeos/química , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Feminino , Ácido Glicirretínico/química , Células Hep G2 , Humanos , Neoplasias Hepáticas Experimentais/patologia , Ratos Wistar
3.
Int J Nanomedicine ; 15: 537-552, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32021193

RESUMO

Background: Synergistic chemoradiotherapy (CRT) has become a primary effective curative approach for many solid cancers. However, CRT is still associated with several obstacles, including the increases in side effects and systemic toxicity. Incorporating nanocarriers into CRT is a new and exciting approach to solve these obstacles. The purpose of the present study was to design a unique pH- and ultrasound-responsive perfluoropentane-encapsulated, paclitaxel (PTX)-loaded carboxymethyl chitosan nanodroplets (NDs) for combined imaging and synergistic CRT. Materials and Methods: The NDs were prepared by a homogenization/emulsion method. Their physicochemical properties, echogenicity and biocompatibility were evaluated. PTX-loaded NDs with a high loading efficiency and encapsulation efficiency were prepared and their pH-responsive drug release profile was determined by dialysis sack method. Then, PC3 cells were exposed to (1) PTX (4 µg/mL), (2) NDs (30 µg/mL), (3) PTX-loaded NDs (34 µg/mL), (4) RT (6 Gy), (5) RT (10 Gy), (6) combination of PTX (4 µg/mL), ultrasound (0.5 W/cm2, 30 s) and RT (6 Gy), (7) combination of NDs (30 µg/mL), ultrasound (0.5 W/cm2, 30 s) and RT (6Gy), (8) combination of PTX-loaded NDs (30 µg/mL), ultrasound (0.5 W/cm2, 30 s) and RT (6 Gy). 24 hrs later, CCK-8 assay, flow cytometry and migration assay were carried out to evaluate their therapeutic effects in CRT. Results: The desired NDs were successfully prepared, which were with round, spherical shapes, relatively smooth surfaces, core-shell structures and uniform in sizes (<300 nm with PDI<0.3 when at pH≧6.0). The NDs exhibited good abilities in pH-dependent charge conversion, biocompatibility and ultrasound contrast echogenicity. The in vitro drug release from PTX-loaded NDs (the highest loading efficiency and encapsulation efficiency were 20.35% and 91.58%) was pH dependent and exhibited an initial burst followed by a sustained drug release. The results of the CCK-8 assay, flow cytometry and migration assay all showed PTX-loaded NDs combined ultrasound and RT significantly enhanced cell responses in CRT. Conclusion: The pH- and ultrasound-responsive PTX-loaded NDs, which exhibited a high echogenicity, drug delivery ability and radiosensitization ability, could be a feasible option for combined imaging and novel enhancing approach in synergistic CRT.


Assuntos
Quitosana/análogos & derivados , Nanoestruturas/administração & dosagem , Paclitaxel/administração & dosagem , Linhagem Celular Tumoral , Quimiorradioterapia/métodos , Quitosana/química , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Fluorcarbonetos/química , Humanos , Concentração de Íons de Hidrogênio , Masculino , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Paclitaxel/química , Paclitaxel/farmacocinética , Tamanho da Partícula , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Ultrassonografia
4.
Food Chem ; 315: 126288, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32032833

RESUMO

ß-Carotene was encapsulated in the Pickering emulsions stabilized by chitosan hydrochloride - carboxymethyl starch (CHC-CMS) nanogels. During ultraviolet radiation and storage, the retention of ß-carotene in Pickering emulsions was higher than that of other formulations, such as Tween 80 stabilized emulsions (TEs) and bulk oil. The Pickering emulsions were found to be stable during thermal treatment. Meanwhile, lipid oxidation was delayed in Pickering emulsions compared to TEs and bulk oil. The vitro digestion results suggested that the free fatty acids (FFA) released were below 30% for all Pickering emulsions, which indicated that a physical barrier was formed by CHC-CMS nanogels to restrain the lipid hydrolysis. The bioaccessibility of ß-carotene in Pickering emulsions was higher than that in bulk oil. This research helped establish a connection between the physicochemical properties of CHC-CMS stabilized Pickering emulsions with their applications in the protection effect and oral delivery of bioactive compounds.


Assuntos
Quitosana/química , beta Caroteno/química , Quitosana/análogos & derivados , Emulsões/química , Ácido Clorídrico/química , Hidrólise , Lipídeos/química , Nanogéis/química , Oxirredução , Tamanho da Partícula , Amido/análogos & derivados , Raios Ultravioleta
5.
Biochemistry (Mosc) ; 85(Suppl 1): S154-S176, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32087058

RESUMO

In this review, we present the data on the natural occurrence of chitin and its partially or fully deacetylated derivative chitosan, as well as their properties, methods of modification, and potential applications of derivatives with bactericidal, fungicidal, and antioxidant activities. The structure and physicochemical characteristics of the polymers, their functions, and features of chitin microbial synthesis and degradation, including the processes occurring in nature, are described. New data on the hydrolytic microorganisms capable of chitin degradation under extreme conditions are presented. Special attention is focused on the effect of physicochemical characteristics of chitosan, including molecular weight, degree of deacetylation, polydispersity index, and number of amino group derivatives (quaternized, succinyl, etc.) on the antimicrobial and antioxidant properties of modified polymers that can be of particular interest for biotechnology, medicine, and agriculture. Analysis of the available literature data confirms the importance of fundamental research to broaden our knowledge on the occurrence of chitin and chitosan in nature, their role in global biosphere cycles, and prospects of applied research aimed at using chitin, chitosan, and their derivatives in various aspects of human activity.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Quitosana/análogos & derivados , Quitosana/farmacologia , Fungicidas Industriais/farmacologia , Antibacterianos/química , Antibacterianos/metabolismo , Antifúngicos/química , Antifúngicos/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Bactérias/metabolismo , Biotecnologia , Quitosana/química , Quitosana/metabolismo , Proteção de Cultivos , Descoberta de Drogas , Fungicidas Industriais/química , Fungicidas Industriais/economia , Fungicidas Industriais/metabolismo , Humanos , Hidrólise , Peso Molecular , Polímeros
6.
Int J Mol Sci ; 21(2)2020 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-31940963

RESUMO

Chitosan is a product of the deacetylation of chitin, which is widely found in nature. Chitosan is insoluble in water and most organic solvents, which seriously limits both its application scope and applicable fields. However, chitosan contains active functional groups that are liable to chemical reactions; thus, chitosan derivatives can be obtained through the chemical modification of chitosan. The modification of chitosan has been an important aspect of chitosan research, showing a better solubility, pH-sensitive targeting, an increased number of delivery systems, etc. This review summarizes the modification of chitosan by acylation, carboxylation, alkylation, and quaternization in order to improve the water solubility, pH sensitivity, and the targeting of chitosan derivatives. The applications of chitosan derivatives in the antibacterial, sustained slowly release, targeting, and delivery system fields are also described. Chitosan derivatives will have a large impact and show potential in biomedicine for the development of drugs in future.


Assuntos
Antibacterianos/síntese química , Quitosana/análogos & derivados , Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Solubilidade
7.
DNA Cell Biol ; 39(3): 451-458, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31910350

RESUMO

Gene delivery from tissue engineering scaffold is a novel strategy in regulating long-term growth and function of cells in vitro culture. In this study, a hepatocyte growth factor plasmid/polyetherimide (pHGF/PEI) polyplex delivering alginate (AL)/galactosylated chitosan (GC) (pHGF/PEI-AL/GC) sponge scaffold was prepared for the in vitro coculture of hepatocytes/3T3 cells. The pHGF/PEI polyplex released for 6 days in the sponge scaffold with weight ratio of AL/GC being 3:1 and fixed amount of pHGF being 40 µg (24-well scaffold). In addition, the 3T3 cells culturing in the pHGF/PEI-AL/GC sponge scaffold could be continually transfected and expressed the exogenous HGF for 6 days. Furthermore, the albumin secretion and urea synthesis of hepatocytes were significantly enhanced when cocultured with 3T3 cells in the pHGF/PEI-AL/GC sponge scaffold compared with that in the AL/GC sponge without pHGF. In summary, the preparation of AL/GC sponge scaffold delivering pHGF/PEI polyplex is a critical significance for maintaining the long-term survival and function of primary hepatocytes in vitro.


Assuntos
Quitosana/análogos & derivados , Técnicas de Transferência de Genes , Fator de Crescimento de Hepatócito/metabolismo , Hepatócitos/metabolismo , Tecidos Suporte/química , Células 3T3 , Alginatos/química , Animais , Células Cultivadas , Técnicas de Cocultura/métodos , Galactose/análogos & derivados , Fator de Crescimento de Hepatócito/genética , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Masculino , Camundongos , Polímeros/química , Ratos , Ratos Wistar , Tecidos Suporte/efeitos adversos
8.
Carbohydr Polym ; 231: 115678, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888806

RESUMO

A simple method was proposed for preparing the dialdehyde-ß-cyclodextrin (DA-ß-CD) cross-linked carboxymethyl chitosan (CMCS) hydrogels for drug delivery. DA-ß-CD was yielded from the sodium periodate oxidation of ß-CD. Phenolphthalein (PhP) was adopted as a model drug to study the drug loading and releasing properties of the obtained hydrogels. The results show that the ability of the hydrogel to load drug is affected by the aldehyde content of DA-ß-CD. The inclusion constant of DA-ß-CD toward PhP is lower than that of the original ß-CD and decreased with the rising of the aldehyde content. An increased cross-linking degree between DA-ß-CD and CMCS slows the PhP release to some extent. In comparison with glyoxal/CMCS, DA-ß-CD/CMCS presents better PhP release properties. Only 19.2 % of PhP loaded in glyoxal/CMCS was released within 24 h. Half of PhP loaded in DA-ß-CD/CMCS was released in 2 h and about 90 % was released within 12 h.


Assuntos
Quitosana/análogos & derivados , Quitosana/química , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Quitosana/farmacologia , Reagentes para Ligações Cruzadas/química , Liberação Controlada de Fármacos , Glioxal/química , Humanos , Hidrogéis/farmacologia , beta-Ciclodextrinas/química
9.
Carbohydr Polym ; 231: 115681, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888851

RESUMO

Electrospun polycaprolactone/carboxymethyl chitosan (PCL/CMC) nanofibers treated by helium cold atmospheric plasma (CAP) and grafted with bone morphogenic protein-2 (BMP-2) were used scaffolds for the osteodifferentiation of stem cells to. For in vitro study, human bone marrow-derived mesenchymal stem cells (hMSCs) were cultured on these scaffolds, and their behaviors were assessed via optical microscopy, MTT assay, and SEM. The osteogenic differentiation of the hMSCs was evaluated by calcium content and alkaline phosphatase assays, Alizarin red and immunofluorescence (ICC) staining, and RT-PCR. The results showed that scaffolds not only can support the proliferation of hMSCs but also can promote their differentiation to osteoblasts without using any external osteogenic differential agent. The RT-PCR and ICC data revealed that the CAP treatment and BMP-2-functionalization have synergic enhancement on the ossification of hMSCs. These fabricated scaffolds can be used as promising candidates for bone tissue engineering applications.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Quitosana/análogos & derivados , Osteogênese/efeitos dos fármacos , Gases em Plasma/farmacologia , Proteína Morfogenética Óssea 2/genética , Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Quitosana/química , Quitosana/farmacologia , Humanos , Células-Tronco Mesenquimais , Nanofibras/química , Osteoblastos/efeitos dos fármacos , Osteoblastos/efeitos da radiação , Engenharia Tecidual
10.
Carbohydr Polym ; 230: 115635, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887858

RESUMO

In this study, 6-deoxy-6-arginine modified chitosan (DAC), was synthesized and characterized by Fourier Transform Infrared Spectroscopy (FTIR), 1H and 13C nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC) and elemental analysis. The arginine was grafted onto C6 groups of chitosan. Antibacterial activity of DAC against gram-negative bacteria Escherichia coli (E. coli) and gram-positive bacteria Staphylococcus aureus (S. aureus) were investigated at concentration between 0.02 mg/mL and 10 mg/mL. Cell viability assessment was estimated in vitro with Caco-2 and L929 cells. Water solubility of DAC at different pH was also evaluated. The results showed that the minimum inhibitory concentration (MICs) of DAC against S. aureus and E. coli were 0.078 mg/mL and 0.312 mg/mL, respectively. The minimum bactericidal concentration (MBC) against S. aureus and E. coli was 0.625 mg/mL. The cytotoxicity of chitosan and DAC was not significantly different. It demonstrated that DAC might be a potential safe antibacterial agent.


Assuntos
Antibacterianos , Quitosana , Antibacterianos/química , Antibacterianos/farmacologia , Arginina/química , Células CACO-2 , Quitosana/análogos & derivados , Quitosana/química , Quitosana/farmacologia , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana/métodos , Solubilidade , Staphylococcus aureus/efeitos dos fármacos
11.
Carbohydr Polym ; 230: 115625, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887856

RESUMO

A new positively charged nanoemulsion using quaternized chitosan (QCS) as a protective layer was developed to improve the stability and bioactivity of lipophilic active components. The anti-inflammatory Plai extract was chosen as both an active ingredient and an oil phase of the system. Compared with chitosan-coated nanoemulsion (NE2-CS) and uncoated nanoemulsion (NE1), the QCS coating could improve the stability of the Plai extract during 28 days. The particle size of NE1 increased from 141 nm to 202 nm after coating with QCS, whereas zeta potential changed from -22.03 mV for NE1 to 20.23 mV for NE2-QCS, confirming the presence of QCS. A clear improvement in anti-inflammatory, anti-cancer, and transdermal properties of Plai extract was verified for NE2-QCS, which could be due to the NEs' fineness and the permanent positive charge of the protective layer. Therefore, we suggested that QCS-coated NEs can be used as an effective transdermal delivery system for lipophilic active components.


Assuntos
Anti-Inflamatórios/administração & dosagem , Antineoplásicos/administração & dosagem , Quitosana/análogos & derivados , Nanopartículas/química , Extratos Vegetais/administração & dosagem , Absorção Cutânea , Zingiberaceae/química , Anti-Inflamatórios/farmacocinética , Antineoplásicos/farmacocinética , Linhagem Celular , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Emulsões/química , Humanos , Extratos Vegetais/farmacocinética , Eletricidade Estática
12.
Carbohydr Polym ; 230: 115600, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887872

RESUMO

Kinetics of chitosan depolymerization were studied in dilute acetic acid solution, in presence of H-Mordenite (H-MOR). Rate constants for chitosan depolymerization were determined by measurement of molecular weight, using Gel permeation Chromatography (GPC). Depolymerization rate of chitosan was altered in presence of an acidic, porous material like H-MOR. Maximum concentration of H-MOR studied during process led to minimal increase in energy of activation, from 20.54 kJ/moL to 23.25 kJ/moL. Infra-red spectroscopy, adsorption studies and rheological assessment indicated adsorption /grafting of chitosan onto porous H-MOR surface as the possible mechanism for facilitation of the depolymerization process. Under extreme conditions investigated during process optimization, H-MOR resulted in a three-fold reduction in 5-Hydroxy Methyl Furfural (5-HMF) formation and over ten times decrease in glucosamine content, as compared to reactions conducted without H-MOR. Therefore, presence of H-MOR is imperative to cleave chitosan in controlled manner and obtain products of desired molecular weight, with fewer impurities.


Assuntos
Silicatos de Alumínio/química , Quitosana/análogos & derivados , Ácidos/química , Química Verde/métodos , Cinética , Polimerização
13.
Carbohydr Polym ; 230: 115614, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887875

RESUMO

Fluorescent bioprobs are in urgent demand to monitor important biological events in biomedicine. However, the aggregation-caused quenching character, high toxicity, water-insolubility and easy leakage property of conventional small molecular dyes hinder the development in this area. In this work, an aggregation-induced emission (AIE) bioconjugate was synthesised by labeling tetraphenylethylene (TPE) to quaternized chitosan (QCS). The TPE-QCS bioconjugate emits strong fluorescence even in solid state, and is cationic and water-soluble over a wide range of pH values. The TPE-QCS aqueous solution stained HeLa cells by dose- and time-depent manner and imaged living cells with bright fluorescence. Futhermore, the cationic bioconjugate was readily internalized by cells through endocytosis, and further aggragated to large sizes and adhered to negatively charged organelle membranes inside cells achieving fluorescent cell imaging with fluorescence enhancement and leakage-free staining. The AIE-active TPE-QCS with cationic nature, good water-solubility over a wide pH range and unique cell imaging properties could trace HeLa cells for as long as 23 passages, that was obviously superior to existing commercial cellular tracer, so has promising application prospects as ultra long-term tracer in biomedical field.


Assuntos
Quitosana/análogos & derivados , Corantes Fluorescentes/química , Nanoconjugados/química , Células 3T3 , Absorção de Radiação , Animais , Cátions/química , Endocitose , Células HeLa , Humanos , Camundongos , Polimerização , Solubilidade , Estilbenos/química , Raios Ultravioleta
14.
Carbohydr Polym ; 230: 115606, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887878

RESUMO

In this research, biocomposite films containing chitosan (CS), polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP), with different ratios, have been provided. The effects of adding hexamethylene 1, 6-di(aminocarboxysulfonate) (HMDACS) as cross-linking agent and the formation of urethane linkage on mechanical properties such as tensile strength, elongation and dynamic-mechanical properties such as storage modulus and tan δ were studied. Also, the antibacterial properties of the composites were investigated by viable bacterial cell counting and compared in reducing the bacterial growth. The final results showed the composite containing CS (50 wt%), PVA (30 wt%), PVP (20 wt%) and HMDACS (2 wt%) had the highest mechanical properties. Scanning electron microscopy (SEM) micrographs confirmed uniform distribution of components in the polymer matrix. In general, low contact angle values revealed the hydrophilicity of the prepared films. It was found that the composites made by combining CS, PVA and PVP at concentration of 50, 25, 25 wt% (A3) and 60, 20, 20 wt% (B4), cross-linked with 2 wt% HMDACS, had the best antibacterial activity against Escherichia coli and Staphylococcus aureus, hence they can be used as promising materials for the preparation of wound dressings.


Assuntos
Curativos Hidrocoloides , Quitosana/análogos & derivados , Nanocompostos/química , Uretana/química , Antibacterianos/química , Antibacterianos/farmacologia , Reagentes para Ligações Cruzadas/química , Escherichia coli/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Polivinil/química , Staphylococcus aureus/efeitos dos fármacos
15.
Carbohydr Polym ; 230: 115602, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887886

RESUMO

Chitosan nanoparticles (CNP) were synthesized via ionic gelation and used for the preparation of starch-based nanocomposite films containing different concentration of CNP (0, 5, 10, 15, 20% w/w). Antimicrobial properties of starch/CNP films was evaluated via in vitro (disc diffusion analysis) and in vivo (microbial count in wrapped cherry tomatoes) study. It was found that inhibitory zone of the 15 and 20% of starch/CNP films were clearly observed for all the tested bacteria including Bacillus cereus, Staphylococcus aureus, Escherichia coli and Salmonella typhimurium. In vivo study revealed that the starch/CNP film (15% w/w) was more efficient to inhibit the microbial growth in cherry tomatoes (7 × 102 CFU/g) compared to neat starch film (2.15 × 103 CFU/g) thus confirmed the potential application of the films as antimicrobial food packaging.


Assuntos
Anti-Infecciosos/química , Quitosana/análogos & derivados , Filmes Comestíveis , Nanopartículas/química , Amido/química , Anti-Infecciosos/farmacologia , Embalagem de Alimentos/métodos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos
16.
Carbohydr Polym ; 230: 115617, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887888

RESUMO

Oral controlled release formulations have been at the center of pharmaceutical research over several decades due to their distinct advantages compared to conventional dosage forms where the entire drug payload is released and absorbed rapidly following administration. Natural polysaccharides are extensively being studied as release modifiers in oral controlled release dosage forms because of their biocompatibility, biodegradability, good safety profile, low-cost availability, and production from renewable resources. Furthermore, polysaccharides can be easily modified by physical or chemical processes to suit specific needs. This article critically reviews some of the important natural polysaccharides with emphasis on their structure, major sources, properties, and applications in various oral modified release systems. The underlying drug release mechanisms from different dosage forms are also discussed. Finally, we outline the critical limitations and challenges that need to be addressed for promoting extensive applications of natural polysaccharides in commercial controlled-release formulations.


Assuntos
Alginatos/química , Celulose/análogos & derivados , Quitosana/análogos & derivados , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Polímeros Responsivos a Estímulos/química , Administração Oral , Animais , Humanos
17.
Carbohydr Polym ; 230: 115613, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887935

RESUMO

Targeted and sensitive drug release at the colitis site is critical for the effective therapy of ulcerative colitis and reduction of side effects from the drug. Herein, we used 3,3'-dithiodipropionic acid (DTPA) to covalently link quercetin (Qu) and glyceryl caprylate-caprate (Gcc) via ester bonds to prepare Qu-SS-Gcc lipid nanoparticles (Qu-SS-Gcc LNPs). Dexamethasone (Dex) was used as a model drug, and chitosan (CSO) was modified on the surface of Qu-SS-Gcc LNPs to obtain CSO-modified Dex-loaded Qu-SS-Gcc LNPs (CSO/Dex/LNPs). The encapsulation efficiency and drug loading of CSO/Dex/LNPs were 93.1 % and 8.1 %, respectively. The in vitro release results showed that CSO/Dex/LNPs had esterase-responsive characteristics and could release the drug rapidly in esterase-containing artificial intestinal fluid. A human colorectal adenocarcinoma cell (Caco-2) monolayer was used as the intestinal cell barrier model. Transmembrane resistance measurements and permeation experiments showed that CSO/Dex/LNPs had a protective effect on the lipopolysaccharide (LPS)-stimulated Caco-2 cell monolayer and increased the expression of E-cadherin in LPS-stimulated Caco-2 cells. Moreover, CSO/Dex/LNPs could significantly reduce the expression of the inflammatory factors TNF-α, IL-6 and NO in LPS-stimulated RAW 264.7 cells. The ulcerative colitis mouse model was constructed by using C57BL/6 mice. The in vivo distribution results showed that CSO/Dex/LNPs had colon-targeting effects and strong retention ability in the colons of mice with colitis. The results also showed that CSO/Dex/LNPs had better anti-inflammatory effects than free Dex, which could reduce colonic atrophy, reduce histomorphological changes and increase the expression of E-cadherin in the colon. Furthermore, the expression levels of TNF-α, IL-6 and NO in the CSO/Dex/LNP-treated group were 37.4 %, 35.5 % and 33.2 % of those in mice with colitis, respectively.


Assuntos
Caprilatos/química , Quitosana/análogos & derivados , Colite Ulcerativa/tratamento farmacológico , Portadores de Fármacos/química , Nanopartículas/química , Polímeros Responsivos a Estímulos/química , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Células CACO-2 , Colo/efeitos dos fármacos , Colo/metabolismo , Reagentes para Ligações Cruzadas/química , Citocinas/genética , Citocinas/metabolismo , Dexametasona/administração & dosagem , Dexametasona/uso terapêutico , Portadores de Fármacos/efeitos adversos , Esterases/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/efeitos adversos , Óxido Nítrico/metabolismo , Quercetina/administração & dosagem , Quercetina/química , Quercetina/uso terapêutico , Células RAW 264.7
18.
Carbohydr Polym ; 230: 115627, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887941

RESUMO

In this study, chitosan (C) tripolyphosphate (T) sub-micro particles containing ungeremine (CTUn), an alkaloid particularly active against Penicilliumroqueforti, a fungus responsible of the bakery products deterioration, were prepared through external gelation crosslinking process. The particles were included in a thermoplastic starch based polymer Mater-Bi (MBi), and MBi/CTUn bioactive biocomposites were obtained. The films showed bioactivity against P. roqueforti. In particular, the bioassays were performed on films with different concentration of CTUn and at different pH values. CTUn particles influenced MBi crystallization (DSC analysis) and promoted thermal degradation of MBi starch component (TGA). Morphological analysis confirmed even distribution of sub-micro particles into the polymeric matrix. Water permeability slightly increased, as expected, whereas oxygen permeability decreased. Tensile tests showed CTUN sub-microparticles improved rigidity and tensile strength of the films at the expense of ductility. Finally, MBi/CTUn biocomposites evidenced interesting performances potentially exploitablein bioactive bakery based food packaging materials.


Assuntos
Antifúngicos/química , Quitosana/análogos & derivados , Amido/análogos & derivados , Antifúngicos/farmacologia , Embalagem de Alimentos/métodos , Nanocompostos/química , Oxigênio/química , Penicillium/efeitos dos fármacos , Resistência à Tração
19.
Carbohydr Polym ; 230: 115610, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887960

RESUMO

This work describes a novel delivery system for targeting egg-derived anti-inflammatory tripeptide Ile-Arg-Trp (IRW) to endothelial cells. The nanomedicine is synthesized by a simple and reproducible ionotropic gelification method that results in the efficient loading of the positively charged IRW within the dermatan sulfate/ chitosan matrix, as demonstrated by ss-NMR spectroscopy. The incorporation of IRW results in a stable nanoparticle dispersion with a single size population of 442 ±â€¯43 nm. Fluorescence microscopy studies demonstrate the capacity of the nanomaterial to distinguish between a quiescent and an injured endothelium through the interaction of dermatan sulfate with the CD44 receptor. Remarkably, no additional surface functionalization is required as dermatan sulfate mediates their internalization and the intracellular release of this natural anti-inflammatory tripeptide to modulate endothelial inflammatory response. This simple, scalable, and versatile nanotechnology platform opens new opportunities to apply in the therapy of vascular disease.


Assuntos
Anti-Inflamatórios/administração & dosagem , Quitosana/análogos & derivados , Dermatan Sulfato/química , Nanopartículas/química , Oligopeptídeos/administração & dosagem , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Células Cultivadas , Liberação Controlada de Fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Camundongos , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Ligação Proteica
20.
Food Chem ; 311: 125878, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31771910

RESUMO

ß-Carotene is a natural nutrient that serves as a natural food colorant. However, the weak physical stability restricts its development in food industrial production. Here, the influences of a variety of external environmental conditions on the stability of ß-carotene enriched zein-carboxymethyl chitosan (CMCS)-tea polyphenols (TP) ternary composite nanoparticles were investigated. Compared with zein unitary and zein-CMCS binary complexes, it was interesting to note that ternary complexes had the best stability against color fading and there was little impact on its nanoparticle size during storage with change in temperature. Besides excellent antioxidant properties, ternary complexes were extremely effective in inhibiting ß-carotene color degradation when exposed to ultraviolet light. Based on our results, the novel zein-CMCS-TP nanoparticles are expected to be an effective delivery system to encapsulate hydrophobic bioactive compounds, which is a promising approach to improve their storage stability against external environmental stresses.


Assuntos
Quitosana/análogos & derivados , Nanopartículas/química , Polifenóis/química , Zeína/química , beta Caroteno/química , Antioxidantes/química , Quitosana/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Concentração Osmolar , Tamanho da Partícula , Chá/química , Temperatura , Raios Ultravioleta
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