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1.
Int J Nanomedicine ; 15: 4877-4898, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32753869

RESUMO

Background: Although dynamics and uses of modified nanoparticles (NPs) as orally administered macromolecular drugs have been researched for many years, measures of molecule stability and aspects related to important transport-related mechanisms which have been assessed in vivo remain as relatively under characterized. Thus, our aim was to develop a novel type of oral-based delivery system for insulin and to overcome barriers to studying the stability, transport mechanisms, and efficacy in vivo of the delivery system. Methods: NPs we developed and tested were composed of insulin (INS), dicyandiamide-modified chitosan (DCDA-CS), cell-penetrating octaarginine (r8), and hydrophilic hyaluronic acid (HA) and were physically constructed by electrostatic self-assembly techniques. Results: Compared to free-insulin, levels of HA-DCDA-CS-r8-INS NPs were retained at more desirable measures of biological activity in our study. Further, our assessments of the mechanisms for NPs suggested that there were high measures of cellular uptake that mainly achieved through active transport via lipid rafts and the macropinocytosis pathway. Furthermore, investigations of NPs indicated their involvement in caveolae-mediated transport and in the DCDA-CS-mediated paracellular pathway, which contributed to increasing the efficiency of sequential transportation from the apical to basolateral areas. Accordingly, high efficiency of absorption of NPs in situ for intestinal loop models was realized. Consequently, there was a strong induction of a hypoglycemic effect in diabetic rats of NPs via orally based administrations when compared with measures related to free insulin. Conclusion: Overall, the dynamics underlying and influenced by HA-DCDA-CS-r8-INS may hold great promise for stability of insulin and could help overcome interference by the epithelial barrier, and thus showing a great potential to improve the efficacy of orally related treatments.


Assuntos
Quitosana/química , Ácido Hialurônico/química , Insulina/administração & dosagem , Nanopartículas Multifuncionais/química , Nanopartículas/química , Administração Oral , Animais , Transporte Biológico/efeitos dos fármacos , Células CACO-2 , Morte Celular/efeitos dos fármacos , Quitosana/síntese química , Diabetes Mellitus Experimental/tratamento farmacológico , Impedância Elétrica , Endocitose/efeitos dos fármacos , Guanidinas/síntese química , Guanidinas/química , Humanos , Ácido Hialurônico/síntese química , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacologia , Insulina/uso terapêutico , Absorção Intestinal/efeitos dos fármacos , Masculino , Muco/metabolismo , Nanopartículas/ultraestrutura , Ratos , Solubilidade , Suínos
2.
AAPS PharmSciTech ; 21(6): 233, 2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32794119

RESUMO

Endolysins are a novel class of antibacterials with proven efficacy in combating various bacterial infections, in vitro and in vivo. LysMR-5, an endolysin derived from phage MR-5, demonstrated high lytic activity in our laboratory against multidrug-resistant S. aureus (MRSA) and S. epidermidis strains. However, endolysin and proteins in general are associated with instability and short in vivo half-life, consequently limiting their usage as pharmaceutical preparation to treat bacterial infections. Nanoencapsulation of endolysins could help to achieve better therapeutic outcome, by protecting the proteins from degradation, providing sustained release, thus could increase their stability, shelf life, and therapeutic efficacy. Hence, in this study, the feasibility of alginate-chitosan nanoparticles (Alg-Chi NPs) to serve as drug delivery platform for LysMR-5 was evaluated. LysMR-5-loaded nanoparticles were prepared by calcium ion-induced pre-gelation of alginate core and its complexation with chitosan. The formation of nanoparticles was confirmed on the basis of DLS, zeta potential, and electron microscopy imaging. The LysMR-5-loaded nanoparticles presented a hydrodynamic diameter of 276.5 ± 42, a PDI of 0.342 ± 0.02, a zeta potential - 25 mV, and an entrapment efficiency of 62 ± 3.1%. The potential ionic interaction between alginate, chitosan, and LysMR-5 was investigated by FT-IR and SEM-EDX analysis. Using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), nano-sized particles with characteristic morphology were seen. Different antibacterial assays and SDS-PAGE analysis showed no change in endolysin's structural integrity and bioactivity after entrapment. A direct antibacterial effect of blank Alg-Chi Nps, showing enhanced bactericidal activity upon LysMR-5 loading, was observed against S. aureus. At physiological pH (7.2), the release profile of LysMR-5 from Alg-Chi NPs showed a biphasic release and followed a non-Fickian release mechanism. The biocompatible nature as revealed by cytocompatibility and hemocompatibility studies endorsed their use as drug delivery system for in vivo studies. Collectively, these results demonstrate the potential of Alg-Chi NPs as nano-delivery vehicle for endolysin LysMR-5 and other therapeutic proteins for their use in various biomedical applications.


Assuntos
Alginatos/síntese química , Quitosana/síntese química , Nanopartículas/química , Infecções Estafilocócicas , Staphylococcus aureus/efeitos dos fármacos , Alginatos/administração & dosagem , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Quitosana/administração & dosagem , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos/métodos , Endopeptidases/administração & dosagem , Endopeptidases/síntese química , Previsões , Humanos , Camundongos , Nanopartículas/administração & dosagem , Tamanho da Partícula , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/fisiologia
3.
Carbohydr Polym ; 231: 115684, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888826

RESUMO

We developed a rapid and precise method to determine the fraction of acetylation (FA) of unknown chitosan samples using a combination of enzymatic sample hydrolysis, isotopic labeling, and HILIC-ESI-MS analysis. Chitosans are ß-(1,4)-linked, partially N-acetylated and linear polyglucosamines representing an interesting group of functional biopolymers with a broad range of applications. For a better understanding of their structure-function relationships, it is key to have sensitive, accurate structural analysis tools available to determine parameters like the degree of polymerization (DP), fraction of acetylation (FA), or pattern of acetylation (PA). Here, we describe an improved enzymatic/mass spectrometric method for FA analysis of chitosan polymers. In contrast to the original chitinosanase-based mass spectrometric fingerprinting analysis of FA, the new method is independent of the PA and the intermolecular variation in FA (DFA) of the chitosan sample. This allows accurate analysis of heterogeneously de-N-acetylated samples representing the majority of commercially available chitosans.


Assuntos
Biopolímeros/química , Quitina/química , Quitosana/química , Glucosamina/análogos & derivados , Acetilação , Quitina/síntese química , Quitosana/síntese química , Glucosamina/química , Hidrólise , Marcação por Isótopo , Espectrometria de Massas , Muramidase/química
4.
Carbohydr Polym ; 231: 115744, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888854

RESUMO

Chitosan with abundant functional groups is regarded as important ingredients for preparing aerogel materials in life science. The biocompatibility and biodegradability of chitosan aerogels, coupled to the variety of chemical functionalities they include, result in them promising carriers for drug delivery. Moreover, chitosan aerogels as drug delivery vehicles can offer improved drug bioavailability and drug loading capacity due to their highly porous network, considerably large specific surface area and polycationic feature. The major focus of this review lies in preparation methods of chitosan aerogels from acidic aqueous solution and chitosan solution in Ionic Liquids (ILs). In addition, chitosan aerogels as drug delivery carriers are introduced in detail and expected to inspire readers to create new kind of drug delivery system based on chitosan aerogels. Finally, growing points and perspectives of chitosan aerogels in drug delivery system are given.


Assuntos
Quitosana/química , Sistemas de Liberação de Medicamentos , Géis/química , Quitosana/síntese química , Quitosana/uso terapêutico , Portadores de Fármacos , Géis/síntese química , Géis/uso terapêutico , Humanos , Porosidade , Água/química
5.
Food Chem ; 309: 125513, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31683147

RESUMO

The present study aims at synthesizing and in vitro antibacterial activity evaluation of chitosan oligosaccharide (COS) modified by Cinnamyl alcohol (Cin) onto the OH position of COS. Three different degrees of substitution (DS) COS-O-Cin1-3 were synthesized by changing different molar ratios of COS to Cin. UV-visible spectroscopy (UV-vis), Fourier transform infrared (FT-IR), 1H nuclear magnetic resonance (1H NMR), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and elemental analysis were conducted to characterize the successful synthesis of COS-O-Cin1-3. The results showed that they exhibited higher thermal stability, weaker crystallinity and better antibacterial properties than that of COS. These results aided in obtaining the important supports for exploring new functional antibacterial agents, which expand the scope of COS's application in the food industry.


Assuntos
Quitosana/química , Quitosana/farmacologia , Propanóis/química , Propanóis/farmacologia , Antibacterianos/análise , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/análise , Quitosana/síntese química , Escherichia coli/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Propanóis/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
6.
Chem Commun (Camb) ; 56(6): 908-911, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31850411

RESUMO

Poly(glycerol methacrylate) chitosan nanospheres were facilely one-pot synthesized. For the first time, poly(glycerol methacrylate) with a highly flexible density of hydrophilic molecules grafted on the surface of chitosan was applied to highly specific enrichment of glycopeptides.


Assuntos
Quitosana/química , Glicopeptídeos/análise , Metacrilatos/química , Configuração de Carboidratos , Quitosana/síntese química , Interações Hidrofóbicas e Hidrofílicas , Metacrilatos/síntese química , Nanosferas/química , Tamanho da Partícula , Propriedades de Superfície
7.
Int J Nanomedicine ; 14: 8611-8626, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31802873

RESUMO

Background: Bacterial resistance to antibiotics is a persistent and intractable problem. The sapogenin isolated from the seeds of Camellia oleifera can inhibit antibiotic-resistant bacteria after structural modification. Purpose: This study aims to improve sapogenin's antibacterial activity and avoid bacterial resistance based on nano-preparation with photo responsiveness. Methods: The liposome shell material of carboxymethyl chitosan-phosphatidyl ethanolamine (CMC-PE) was prepared using amidation reaction, and photo-responsive cationic (PCC) liposomes containing Camellia sapogenin derivative (CSD) and photosensitizer pheophorbide-a were prepared by film dispersion method. Encapsulation efficiency, drug loading, zeta potential, particle size distribution, morphology and stability of the PCC liposomes were determined by HPLC, particle size analyzer, transmission electron microscopy (TEM) and fluorescence microscopy. Photo-responsive release of CSD in the PCC liposomes was determined by laser (0.5 mW/cm2) at 665 nm. Antibacterial activity of the PCC liposomes with or without irradiation was analyzed by MIC50, MBC, MBIC50, and bacterial morphology to evaluate the antibacterial effects on amoxicillin resistant Escherichia coli and Staphylococcus aureus. Results: Size distribution, zeta potential, encapsulation efficiency and drug loading of the PCC liposomes were 189.23 ± 2.12 nm, 18.80 ± 1.57 mV, 83.52 ± 1.53% and 2.83 ± 0.05%, respectively. The PCC liposomes had higher storage stability and gastrointestinal stability, and no obvious hemolytic toxicity to rabbit red blood cells and no cytotoxicity after incubation with Hela cells. The photosensitizer pheophorbide-a was uniformly dispersed in the phospholipid layer of the PCC liposomes and increased the CSD release after irradiation. The PCC liposomes could bind to bacteria and impaired their morphology and structure, and had significant bactericidal effect on amoxicillin resistant E. coli and S. aureus. Conclusion: The photo-responsive PCC liposomes are efficient antibacterial agents for avoidance of bacterial resistance against antibiotics.


Assuntos
Antibacterianos/farmacologia , Camellia/química , Quitosana/análogos & derivados , Fármacos Fotossensibilizantes/farmacologia , Sapogeninas/farmacologia , Animais , Cátions/farmacologia , Morte Celular/efeitos dos fármacos , Quitosana/síntese química , Quitosana/química , Quitosana/farmacologia , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Lipossomos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Fosfatidiletanolaminas/síntese química , Fosfatidiletanolaminas/química , Espectroscopia de Prótons por Ressonância Magnética , Coelhos , Staphylococcus aureus/efeitos dos fármacos , Eletricidade Estática
8.
Int J Nanomedicine ; 14: 6917-6932, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695366

RESUMO

Aim: To determine whether the use of a mixed polymeric micelle delivery system based on vitamin E succinate (VES)-grafted-chitosan oligosaccharide (CSO)/VES-grafted-chitosan (CS) mixed micelles (VES-g-CSO/VES-g-CS MM) enhances the delivery of C-DMSA, a theranostic fluorescent probe, for Hg2+ detection and detoxification in vitro and in vivo. Methods: Mixed micelles self-assembled from two polymers, VES-g-CSO and VES-g-CS, were used to load C-DMSA and afforded C-DMSA@VES-g-CSO/VES-g-CS MM for cell and in vivo applications. Fluorescence microscopy was used to assess C-DMSA cellular uptake and Hg2+ detection in L929 cells. C-DMSA@VES-g-CSO/VES-g-CS MM was then administered intravenously. Hg2+ detection was assessed by fluorescence microscopy in terms of bio-distribution while detoxification efficacy in Hg2+-poisoned rat models was evaluated in terms of mercury contents in blood and in liver. Results: The C-DMSA loaded mixed micelles, C-DMSA@VES-g-CSO/VES-g-CS MM, significantly enhanced cellular uptake and detoxification efficacy of C-DMSA in Hg2+ pretreated human L929 cells. Evidence from the reduction of liver coefficient, mercury contents in liver and blood, alanine transaminase and aspartate transaminase activities in Hg2+ poisoned SD rats treated with the mixed micelles strongly supported that the micelles were effective for Hg2+ detoxification in vivo. Furthermore, ex vivo fluorescence imaging experiments also supported enhanced Hg2+ detection in rat liver. Conclusion: The mixed polymeric micelle delivery system could significantly enhance cell uptake and efficacy of a theranostic probe for Hg2+ detection and detoxification treatment in vitro and in vivo. Moreover, this nanoparticle drug delivery system could achieve targeted detection and detoxification in liver.


Assuntos
Quitosana/química , Fígado/metabolismo , Mercúrio/análise , Micelas , Oligossacarídeos/química , Succímero/química , alfa-Tocoferol/farmacologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Morte Celular/efeitos dos fármacos , Linhagem Celular , Quitosana/síntese química , Liberação Controlada de Fármacos , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Humanos , Inativação Metabólica/efeitos dos fármacos , Masculino , Mercúrio/sangue , Camundongos Endogâmicos BALB C , Nanopartículas/química , Oligossacarídeos/síntese química , Ratos Sprague-Dawley , Succímero/síntese química , alfa-Tocoferol/síntese química , alfa-Tocoferol/química
9.
Mater Sci Eng C Mater Biol Appl ; 105: 110111, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546392

RESUMO

Multiple drug resistant (MDR) has become a major issue in developing countries. MDR bacterial infections lead to significant increase in morbidity, mortality and cost of prolonged treatments. Therefore, designing of strategies for improving the antimicrobial potential of the therapeutic agents are highly required. Metal organic frameworks (MOFs) are highly tunable hybrid material, consist of metal ions linked together by organic bridging ligands have been used as an efficient drug delivery carrier because of their biodegradability, low toxicity and structure integrity upon loading and functionalizing process. Current study was based on the synthesis of chitosan coated MOFs with enhanced contact with S. aureus cell surface. Chitosan is deacetylated derivative of chitin and capable for non-bonding interaction with negatively charged bacterial cell leading to enhanced contact of MOFs with S. aureus. Chitosan coated MOFs were characterized with various techniques such as atomic force microscopy, scanning electron microscopy, DLS, FT-IR, TGA, DSC and Powder X-ray diffraction. They were also studied for their efficacy on resistant S. aureus, results revealed that Vancomycin bactericidal activity significantly increased upon loading in chitosan coated MOFs and caused increased inhibition of resistant S. aureus. AFM analysis of S. aureus strains clearly revealed complete distortion of morphology by treating with chitosan modified drug loaded MOFs. Findings of the current study suggest the potential of chitosan coated MOFs for reversing bacterial resistance against Vancomycin and provide new perspectives for improved antibiotic therapy of infections associated with MDR.


Assuntos
Antibacterianos/farmacologia , Quitosana/síntese química , Materiais Revestidos Biocompatíveis/síntese química , Farmacorresistência Bacteriana/efeitos dos fármacos , Estruturas Metalorgânicas/síntese química , Staphylococcus aureus/efeitos dos fármacos , Vancomicina/farmacologia , Varredura Diferencial de Calorimetria , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Propriedades de Superfície , Termogravimetria , Difração de Raios X
10.
Mater Sci Eng C Mater Biol Appl ; 105: 110086, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546413

RESUMO

Chitosan (CS) has been reported to have utility for various potential applications in biomedicine, tissue engineering, and cosmetics, as well as in the formulation of antibacterial agents because it exhibits a variety of desirable attributes, including low-toxicity, biodegradability, excellent biocompatibility, and broad-spectrum antibacterial activity. However, the full realization of CS's biomedical applications are practically constrained by its poor solubility. The goal of the present study is to prepare hydroxybutyl chitosan (HBCS) and investigate its impacts on immunocompetence, and its antibacterial activity. In the current study, HBCS was synthesized by modifying the hydroxybutyl group on the chitosan molecule using an etherification method. The physicochemical properties of the synthesized HBCS were characterized by various methods. Results showed that hydro-soluble HBCS exhibited excellent hygroscopicity and moisture retention. It was also found that HBCS exhibited notable cytocompatibility when cultured with mouse embryo fibroblasts. HBCS was able regulate immuno-functionality and promote immunocompetence by improving phagocytosis of macrophages and reinforcing lymphocyte activity in vivo and in vitro. Moreover, HBCS was also found to inhibit L-929 cell migration, indicating the impeded migration and metastasis behaviors of fibrosarcoma cells. Additionally, HBCS displayed favorable antimicrobial functionality against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. This study demonstrated that HBCS could in turn lock moisture, can promote immunocompetence activity, can inhibit fibrosarcoma cell migration, and exhibits anti-bacterial functionality. Taken together, these results indicate that HBCS shows substantial promise for applications in cosmetics, biomedicine, and antibacterial therapies.


Assuntos
Antibacterianos , Quitosana/análogos & derivados , Embrião de Mamíferos/imunologia , Escherichia coli/crescimento & desenvolvimento , Fibroblastos/imunologia , Staphylococcus aureus/crescimento & desenvolvimento , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Linhagem Celular Tumoral , Quitosana/síntese química , Quitosana/química , Quitosana/farmacologia , Interações Hidrofóbicas e Hidrofílicas , Masculino , Camundongos , Camundongos Endogâmicos ICR
11.
Carbohydr Polym ; 223: 115061, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426963

RESUMO

In this study, chitosan oligosaccharide (COS)-vanillin imine (COS-Vani Imine)-based dual pH responsive nano-micelles (DPRNs) were synthesized. The resultant DPRNs were used for encapsulating genistein and its ultimate release upon pH change. The overall concept of DPRNs for the targeted delivery of hydrophobic anticancer drugs was successfully demonstrated. The DPRNs were spherical in shape, nanoscale in dimension (71.2-163.4 nm), with dual pH response. The encapsulation/loading of genistein into DPRNs was achieved and the resultant genistein-loaded DPRNs were stable under the physiological pH (˜7.4); under the cancer cell extracellular pH (˜6.8), the amino groups in COS is protonated, thus becoming positively charged, facilitating their adsorption onto negatively charged cancer cells. Under the cancer cell intracellular pH (˜5.0), the genistein-loaded DPRNs were destroyed as a result of the cleavage of pH sensitive benzoic imine, thereby releasing the loaded genistein.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Micelas , Nanoestruturas/química , Oligossacarídeos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Quitosana/síntese química , Quitosana/toxicidade , Portadores de Fármacos/síntese química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Genisteína/química , Genisteína/farmacologia , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Nanoestruturas/toxicidade , Oligossacarídeos/síntese química , Oligossacarídeos/toxicidade
12.
Carbohydr Polym ; 223: 115108, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426968

RESUMO

Development of antimicrobial electrospun nanofibrous mats is one of the most recent trends in the field of food biopackaging. Herein, novel antimicrobial fibrous mats consisting of blend electrospun chitosan (CS)/poly(ε-caprolactone) (PCL) embedded with oregano essential oil (OEO) were fabricated via electrospinning approach and investigated. FE-SEM manifested that as-spun fibers were well-oriented with uniform diameters along their lengths, and AFM displayed the dense nature of the fibrous mats, with surface roughness in the range of 62.9-84.6 nm. The physical interactions and hydrogen bonding between CS/PCL and OEO were verified by FTIR. This novel hybrid mat demonstrated excellent mechanical strength of 14.0 MPa and achieved good water vapor barrier performance. In vitro release assay also revealed that most of plant essential oil loaded fiber mats was remained (56.4-81.7%) after 96 h, demonstrating its durability. Furthermore, the CS/OEO(5%)/PCL nanofiber mats exhibited distinctive antibacterial activity towards Gram-positive (Staphylococcus aureus, Listeria monocytogenes) and Gram-negative (Salmonella enteritidis, Escherichia coli) bacteria. This study gives insights to design new fiber-based antimicrobial nanomaterials of interest in food packaging exploits.


Assuntos
Antibacterianos/farmacologia , Quitosana/farmacologia , Embalagem de Alimentos , Nanofibras/química , Óleos Voláteis/farmacologia , Poliésteres/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Quitosana/síntese química , Quitosana/química , Escherichia coli/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óleos Voláteis/síntese química , Óleos Voláteis/química , Tamanho da Partícula , Poliésteres/síntese química , Poliésteres/química , Salmonella enteritidis/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície
13.
Int J Biol Macromol ; 140: 407-414, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31425760

RESUMO

In this work, the chemical cross-linked interaction between chitosan polymeric chains and synthetic terephthaloyl diisothiocyanate as a cross-linker was accomplished in order to fabricate three dimensional cross-linked chitosan hydrogel. This cross-linked hydrogel with considerable characteristics including high stability and homogeneity in aqueous solution (water) and high porosity was applied as new substrate for generation of new magnetic terephthaloyl thiourea cross-linked chitosan nanocomposite. The features of this new magnetic nanocomposite were characterized by FT-IR, EDX, FE-SEM, TEM and VSM analysis. The Size distribution of nanoparticles according to the size histogram of FE-SEM images was estimated between 30 and 40 nm. The performance of designed magnetic nanocomposite was evaluated by magnetic fluid hyperthermia procedure. Under the alternating magnetic field (AMF), the specific absorption rate (66.92 w·g-1) was determined and as well, its saturation magnetization value was reported 78.43 emu·g-1.


Assuntos
Quitosana/química , Hidrogéis/química , Nanopartículas de Magnetita/química , Neoplasias/terapia , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Quitosana/síntese química , Quitosana/farmacologia , Humanos , Hidrogéis/síntese química , Hidrogéis/farmacologia , Hipertermia Induzida/métodos , Nanocompostos/química , Ácidos Ftálicos/síntese química , Ácidos Ftálicos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tioureia/síntese química , Tioureia/química
14.
Drug Des Devel Ther ; 13: 2437-2457, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440030

RESUMO

Background: A series of novel pyrazolopyrimidine and pyrazololpyridine thioglycosides were synthesized and confirmed via their spectral analyses. Purpose: To evaluate the effect of these anti-metabolic compounds against proliferation of Huh-7 and Mcf-7 as in vitro models of human liver and breast cancers, respectively. Vero cells were used as an example of normal green monkey kidney cells. Methods: The most promising compound was subjected to a nanoformulation by its encapsulation into chitosan nanoparticles to increase its anti-cancerous activity. Nanoformulation was confirmed by TEM and FT-IR to ensure encapsulation and screened for their cytotoxicity against Huh-7 and Mcf-7 cells using MTT colorimetric assay and morphological examination. Genotoxic effect was performed by cellular DNA fragmentation assay. Simulated CompuSyn software (linear interaction effect) was conducted to predict the possible synergistic effect of nanocomposite as anticancerous activity. Apoptotic effect was further analyzed by detection of apoptotic proteins using ELISA assay. Results: The nano preparation was successfully prepared by encapsulation of compound 14 into chitosan nanoparticles, controlled to a size at 105 nm and zeta charges at 40.2 mV. Treatment of Huh-7 and Mcf-7 showed that compound 14 was the most cytotoxic compound on both cancer cell lines where IC50 was 24.59 (9.836 µg/mL) and 12.203 (4.8812 µg/mL) on Huh-7 and Mcf-7 respectively. But IC50 of the nano preparation was 37.19 and 30.68 µg/mL on Huh-7 and Mcf-7, respectively, indicating its aggressiveness on human breast cancer cells as confirmed by DNA fragmentation assay and theoretically by CompuSyn tool. Conclusion: A novel series of pyrazolopyrimidine thioglycosides and pyrazolopyridine thioglycosides were synthesized. Nanoformulation of compound 14 into chitosan nanoparticles demonstrated anticancer activity and can be used as a drug delivery system, but further studies are still required.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Modelos Biológicos , Nanopartículas/química , Purinas/farmacologia , Tioglicosídeos/síntese química , Tioglicosídeos/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Quitosana/síntese química , Quitosana/química , Quitosana/farmacologia , DNA de Neoplasias/efeitos dos fármacos , Relação Dose-Resposta a Droga , Composição de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Tamanho da Partícula , Purinas/síntese química , Purinas/química , Relação Estrutura-Atividade , Propriedades de Superfície , Tioglicosídeos/química , Células Tumorais Cultivadas
15.
Int J Biol Macromol ; 139: 521-530, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377297

RESUMO

Chitosan-1-(mercaptomethyl)-cyclopropane acetic acid (CS-MCA) copolymer was synthesized by amino linkage. The obtained copolymer was characterized by FTIR, 1H NMR, XRD, TGA and SEM. Porous and reticulate morphologies were found on the CS-MCA surface. The effects of pH on the rheological properties of CS-MCA were investigated. On the one hand, the apparent viscosity of CS-MCA indicated a shear-thinning behavior. The graft of MCA enhanced the moduli and the maximum elastic properties were observed at pH = 7.00. The addition of dithiothreitol reduced the viscosity and modulus of CS-MCA hydrogel, and the gelation time, temperature and frequency were obtained in dynamic oscillatory tests. The antibacterial effect of CS-MCA against E. coli was investigated for the inhibition zone and bacterial growth curve. These results showed that CS-MCA had better antibacterial ability than chitosan without modification. Therefore, the rheological behavior and functional activities can be applied for the hydrocolloid gels in food and pharmaceutical applications.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Compostos de Sulfidrila/química , Quitosana/síntese química , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria
16.
Mar Drugs ; 17(8)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374920

RESUMO

Chitin is an abundant polysaccharide primarily produced as an industrial waste stream during the processing of crustaceans. Despite the limited applications of chitin, there is interest from the medical, agrochemical, food and cosmetic industries because it can be converted into chitosan and partially acetylated chitosan oligomers (COS). These molecules have various useful properties, including antimicrobial and anti-inflammatory activities. The chemical production of COS is environmentally hazardous and it is difficult to control the degree of polymerization and acetylation. These issues can be addressed by using specific enzymes, particularly chitinases, chitosanases and chitin deacetylases, which yield better-defined chitosan and COS mixtures. In this review, we summarize recent chemical and enzymatic approaches for the production of chitosan and COS. We also discuss a design-of-experiments approach for process optimization that could help to enhance enzymatic processes in terms of product yield and product characteristics. This may allow the production of novel COS structures with unique functional properties to further expand the applications of these diverse bioactive molecules.


Assuntos
Quitina/química , Quitosana/síntese química , Crustáceos/química , Química Verde/métodos , Amidoidrolases/química , Animais , Quitinases/química , Glicosídeo Hidrolases/química , Resíduos Industriais
17.
Int J Biol Macromol ; 139: 1046-1053, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31404605

RESUMO

Skin wound dressing materials, which can accelerate wound healing and have the synthetic advantages of simplicity, environmental safety, and resource abundance, are becoming a hot topic of research now. Following such a research trend, we prepared novel decanoic acid functionalized chitosan (CSDA) with good solubility by acylation via a facile one-step method. FTIR, 1H NMR, and UV-Vis results demonstrated that alkyl chains were successfully grafted onto C2 positions of chitosan (CS) skeleton through acylation. XRD patterns implied that the crystallinity of CSDA greatly declined due to the introduction of alkyl moieties, favorable for improving water solubility. Conductometric titration results showed that the degrees of substitution of CSDA, CSDA1, and CSDA2 were 41.42, 26.12, and 23.17%, respectively. MTT assay and hemolysis experiments illustrated that all the CSDA samples tested in this work possessed good hemocompatibility (hemolysis rate < 2%) and excellent cytocompatibility (relative cell viability >75%) toward L929 cells. Moreover, CSDA-soaked gauze dressings and full-thickness excisional wound models were employed to estimate the feasibility of CSDA as wound dressing material, and the results displayed that CSDA with the degree of substitution of 41.42% could enhance the wound healing rate to 100% on day 16. Altogether, CSDA might be potential material used as wound dressing.


Assuntos
Bandagens , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Quitosana/síntese química , Quitosana/farmacologia , Ácidos Decanoicos/química , Cicatrização/efeitos dos fármacos , Acilação , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/toxicidade , Técnicas de Química Sintética , Quitosana/química , Quitosana/toxicidade , Hemólise/efeitos dos fármacos , Masculino , Ratos , Solubilidade
18.
Int J Biol Macromol ; 140: 1296-1304, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31465804

RESUMO

The potential of electrospun cellulose acetate/chitosan/single walled carbon nanotubes/ferrite/titanium dioxide (CA/chitosan/SWCNT/Fe3O4/TiO2) nanofibers was investigated for the removal of Cr(VI), As(V), Methylene blue and Congo red from aqueous solutions via the adsorption and photocatalytic reduction processes. The properties of synthesized SWCNT/Fe3O4/TiO2 and fibers were characterized using TEM, SEM, FTIR, XRD, TGA and BET analysis. In adsorption process, the influence of adsorbent type including SWCNT to Fe3O4 ratio, TiO2 to SWCNT/Fe3O4 ratio and SWCNT/Fe3O4/TiO2 concentration as well as the adsorption parameters including pH, contact time, and initial concentration of adsorbates on the Cr(VI), As(V), Methylene blue and Congo red adsorption in a batch mode was investigated. The reusability of nanofibers was also investigated for five adsorption-desorption cycles. The photocatalytic reduction of Cr(VI), As(V), Methylene blue and Congo red was also investigated using various nanofibrous catalysts. The obtained results indicated that the removal of Cr(VI) and As(V) using CA/chitosan/SWCNT/Fe3O4/TiO2 nanofibrous adsorbent via adsorption process could be preferred for the lower concentrations of metal ions. The photocatalytic reduction was an effective method for the Cr(VI), As(V) removal at higher concentrations and degradation of Methylene blue and Congo red under both lower and higher concentrations of azo dyes.


Assuntos
Arsênico/isolamento & purificação , Celulose/análogos & derivados , Quitosana/síntese química , Cromo/isolamento & purificação , Compostos Férricos/química , Nanofibras/química , Nanotubos de Carbono/química , Titânio/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Catálise , Celulose/síntese química , Vermelho Congo/isolamento & purificação , Cinética , Azul de Metileno/isolamento & purificação , Nanofibras/ultraestrutura , Nanotubos de Carbono/ultraestrutura , Análise de Regressão , Soluções , Termogravimetria
19.
Int J Biol Macromol ; 139: 103-113, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31374266

RESUMO

This work describes ultrasound-assisted phenol-yne addition of p-hydroxybenzaldehyde and propargylic ester of betaine hydrochloride giving only 2-((3-(4-formylphenoxy)allyl)oxy)-N,N,N-trimethyl-2-oxoethan-1-aminium chloride as a product at 100kHz 300W in water. The ultrasonic assisted phenol-yne addition was enhanced to chitosan chemistry. Phenolic chitosan derivatives were obtained by treatment of chitosan with o-, m- or p-hydroxybenzaldehyde followed by reduction of the formed CN bound by NaBH4. The phenolic chitosan derivatives (phenolic component) were involved in ultrasound-mediated reaction with propargylic ester of betaine hydrochloride (yne component). The reaction led to betaine chitosan derivatives in different degree of substitution as o-, m- and p-isomers. The phenolic and betaine derivatives were tested as antibacterial agents against E. coli in comparison with reference antibiotic Tetracycline. Betaine derivatives showed high antibacterial activity. The most effective polymer was p-isomer of high substituted betaine derivative and its activity was more than 2 times higher than the activity of Tetracycline. The nanoparticles based on this polymer were obtained by ionic gelation method. They had 2Rh 126nm, ξ-potential 20mV and were more effective than the corresponding chitosan derivative.


Assuntos
Alquinos/química , Quitosana/química , Quitosana/farmacologia , Nanopartículas/química , Fenóis/química , Ondas Ultrassônicas , Água/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Benzaldeídos/química , Betaína/química , Técnicas de Química Sintética , Quitosana/síntese química , Escherichia coli/efeitos dos fármacos , Solubilidade
20.
Int J Biol Macromol ; 139: 153-160, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31356952

RESUMO

A new adsorbent, sulfated crosslinked chitosan (SGCH), has been synthesized for the effective extraction of beryllium ions from their aqueous solutions. In recent times, beryllium extraction has been of great importance because beryllium can be used in many applications such as in nuclear reactor, heat shields, high-technology ceramics, alloys and electronic heat sinks. SGCH has been synthesized by two successive phases. The first is the conversion of chitosan (CH) into non-soluble cross-linked chitosan (GCH) through the interaction between chitosan and glutaraldehyde. The second step is the formation of functional sulfonate groups onto the adsorbent material through the interaction of GCH with chlorosulfonic acid (sulfating agent). The role played by the sulfonate groups in the adsorption process was analyzed using FT-IR and SEM. Also, the role played by the solution pH, time, beryllium concentration and temperature on the batch adsorption process was investigated. Our results point to the successful preparation of SGCH adsorbent with high affinity for beryllium ions. The maximum sorption values of beryllium ions on the investigated biosorbent is 40.6 mg/g. The desorption of the loaded beryllium ions from the SGCH was achieved by using 1.5 M urea acidified by 0.6 M H2SO4.


Assuntos
Berílio/química , Berílio/isolamento & purificação , Quitosana/química , Quitosana/síntese química , Ácidos Sulfônicos/química , Adsorção , Técnicas de Química Sintética , Fatores de Tempo
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