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1.
Int J Mol Sci ; 24(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37569435

RESUMO

Over the past two decades, there has been increasing interest in the use of low-cost and effective sorbents in water treatment. Hybrid chitosan sorbents are potential materials for the adsorptive removal of phosphorus, which occurs in natural waters mainly in the form of orthophosphate(V). Even though there are numerous publications on this topic, the use of such sorbents in industrial water treatment and purification is limited and controversial. However, due to the explosive human population growth, the ever-increasing global demand for food has contributed to the consumption of phosphorus compounds and other biogenic elements (such as nitrogen, potassium, or sodium) in plant cultivation and animal husbandry. Therefore, the recovery and reuse of phosphorus compounds is an important issue to investigate for the development and maintenance of a circular economy. This paper characterizes the problem of the presence of excess phosphorus in water reservoirs and presents methods for the adsorptive removal of phosphate(V) from water matrices using chitosan composites. Additionally, we compare the impact of modifications, structure, and form of chitosan composites on the efficiency of phosphate ion removal and adsorption capacity. The state of knowledge regarding the mechanism of adsorption is detailed, and the results of research on the desorption of phosphates are described.


Assuntos
Quitosana , Poluentes Químicos da Água , Purificação da Água , Humanos , Fosfatos , Quitosana/química , Águas Residuárias , Fósforo , Adsorção , Purificação da Água/métodos , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Cinética
2.
Molecules ; 26(9)2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-34063713

RESUMO

Chitosan has many useful intrinsic properties (e.g., non-toxicity, antibacterial properties, and biodegradability) and can be processed into high-surface-area nanofiber constructs for a broad range of sustainable research and commercial applications. These nanofibers can be further functionalized with bioactive agents. In the food industry, for example, edible films can be formed from chitosan-based composite fibers filled with nanoparticles, exhibiting excellent antioxidant and antimicrobial properties for a variety of products. Processing 'pure' chitosan into nanofibers can be challenging due to its cationic nature and high crystallinity; therefore, chitosan is often modified or blended with other materials to improve its processability and tailor its performance to specific needs. Chitosan can be blended with a variety of natural and synthetic polymers and processed into fibers while maintaining many of its intrinsic properties that are important for textile, cosmeceutical, and biomedical applications. The abundance of amine groups in the chemical structure of chitosan allows for facile modification (e.g., into soluble derivatives) and the binding of negatively charged domains. In particular, high-surface-area chitosan nanofibers are effective in binding negatively charged biomolecules. Recent developments of chitosan-based nanofibers with biological activities for various applications in biomedical, food packaging, and textiles are discussed herein.


Assuntos
Quitosana/química , Cosmecêuticos/química , Embalagem de Alimentos , Têxteis , Aminas/química , Animais , Antibacterianos/química , Anti-Infecciosos/química , Antioxidantes/química , Cristalização , Filmes Comestíveis , Humanos , Nanofibras/química , Nanopartículas/química , Polímeros , Regeneração , Pele/patologia , Pele Artificial , Solubilidade , Engenharia Tecidual , Cicatrização
3.
Ann Ig ; 32(1): 72-80, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31713579

RESUMO

BACKGROUND: Clostridioides difficile a Gram-positive, obliged anaerobic, rod-shaped spore-former bacterium, causes a wide spectrum of diseases, ranging from mild, self-limiting diarrhoea to serious diarrhea. Chitosan, a natural polysaccharide, is largely known for its activity against a wide range of microorganisms. Chitosan, in the form of nanofibrils (nanofibrilated chitosan), consists of separated fibers which can be suspended easily in aqueous media. STUDY DESIGN: This paper, for the first time, aims to evaluate the antimicrobial activity of chitosan nanofibers against C. difficile isolates. METHODS: Chitosan nanofibers were characterized through scanning electron microscopy and atomic force microscopy. Minimum inhibitory concentration and minimum bactericidal concentration of chitosan nanofibers against toxigenic C. difficile isolates (with resistance gene: ermB, tetM and tetW) was determined by the standard broth microdilution method. RESULTS: The Miniumum Inhibitory Concentration of chitosan nanofibers for two toxigenic isolates with resistance genes ermB, tetM and tetW, two toxigenic isolates ermB+ tetM+ and the standard strain ATCC 700057 was similar and equal to 0.25 mg/mL. The minimum bactericidal concentration for all isolates was 0.5 mg/mL. CONCLUSIONS: The results demonstrated that chitosan nanofibers exhibit potent antimicrobial activities against multiple toxigenic C. difficile isolates, and the antibacterial effect of chitosan nanofibers against C. difficile isolates with ermB, tetM and tetW resistance genes indicates that interfering with the synthesis of proteins is not the mechanism of action of chitosan nanofibers.


Assuntos
Antibacterianos , Quitosana , Clostridioides difficile , Nanofibras , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Clostridioides difficile/genética , Farmacorresistência Bacteriana/genética , Fezes/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Nanofibras/ultraestrutura
4.
Int J Mol Sci ; 16(11): 26202-10, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26540046

RESUMO

Chitosan produced by the deacetylation of chitin is a cationic polymer with antimicrobial properties. In this study, we demonstrate the improvement of chitosan properties by nanofibrillation. Nanofiber sheets were prepared from nanofibrillated chitosan under neutral conditions. The Young's modulus and tensile strength of the chitosan NF sheets were higher than those of the chitosan sheets prepared from dissolving chitosan in acetic acid. The chitosan NF sheets showed strong mycelial growth inhibition against dermatophytes Microsporum and Trichophyton. Moreover, the chitosan NF sheets exhibited resistance to degradation by the fungi, suggesting potentials long-lasting usage. In addition, surface-deacetylated chitin nanofiber (SDCNF) sheets were prepared. The SDCNF sheet had a high Young's modulus and tensile strength and showed antifungal activity to dermatophytes. These data indicate that nanofibrillation improved the properties of chitosan. Thus, chitosan NF and SDCNF sheets are useful candidates for antimicrobial materials.


Assuntos
Antifúngicos/química , Antifúngicos/farmacologia , Quitosana , Nanofibras , Quitina/química , Quitosana/química , Módulo de Elasticidade , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanofibras/química , Nanofibras/ultraestrutura , Resistência à Tração
5.
Int J Biol Macromol ; 257(Pt 1): 128634, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38065451

RESUMO

The D. cinnabari plant was loaded into the chitosan (Chn)/polycaprolactone (PCL) nanofibers in two forms: resin (D. cinnabari) and its ethyl acetate fraction. The Chn/PCL, Chn/PCL/D. cinnabari (CPD, 1, 3, and 5 %), and Chn/PCL/ethyl acetate extract D. cinnabari (CPED, 1, 3, and 5 %) showed no toxicity against human dermal fibroblast cells. The lactate dehydrogenase assay results indicated that the toxicity of pour, coated D. cinnabari, and CPED nanofibers were lower than 10 and 15 % after 1 and 3 days, respectively. The antibacterial results showed the inhibition zone for ethyl acetate extract D. cinnabari (ED-3 %), the Chn/PCL-2, and CPED3% nanofibers was 8.1, 7.4, 4.2, 5.1 mm, 12.8, 12.4, 21.7, 17.2 mm, and 24.7, 22.9, 37.1, 30.2 mm against S. aureus, B. subtilis, E. coli, and P. aeruginosa, respectively. The antibacterial activity results showed synergistic effect between the Chn/PCL and ethyl acetate extract D. cinnabari occurred. The diameter of wounds (1.50 × 1.50 cm diameter) made on the dorsal surface of rabbits reduced to 1.50 × 0.70, 0.50 × 0.30, 1.00 × 1.00, 0.60 × 0.50, 0.20 × 0.05, and 0.00 × 0.00 cm in the presence of ordinary gauze dressing, silver sulfadiazine, ED-3 %, Chn/PCL-2, CPD3%, and CPED3%nanofibers, respectively, after 14 days.


Assuntos
Acetatos , Quitosana , Nanofibras , Extratos Vegetais , Animais , Humanos , Coelhos , Quitosana/farmacologia , Staphylococcus aureus , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Cicatrização , Poliésteres/farmacologia
6.
Carbohydr Polym ; 329: 121530, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38286525

RESUMO

Separators are indispensable components in lithium-ion batteries (LIBs), providing efficient pathways for lithium ions to travel and isolating the positive and negative electrodes to avoid short circuits. However, traditional polyolefin-based separators exhibit inferior electrolyte affinities, limited porosities, and low thermal stabilities. In this study, a novel method was developed to prepare chitosan micro/nanofiber membranes as LIB separators using natural materials. The pore sizes of the chitosan micro/nanofibers separators were modulated by changing the diameters of the chitosan fibers. The results demonstrated that the chitosan nanofiber separators (CSNFs) had superior electrolyte uptake (281 %), excellent thermal dimensional stability, and electrochemical performance in LiFePO4/Li half-cell, as indicated by the higher discharge capacity after 100 cycles, and higher rate capacity than commercial Celgard2325 separator. This study paves the way for the fabrication of eco-efficient and environment-friendly separators for high-performance LIBs.

7.
Int J Biol Macromol ; 260(Pt 1): 129272, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38211925

RESUMO

Conductive hydrogels, especially polysaccharide-based ionic conductive hydrogels, have received increasing interest in the field of wearable sensors due to their similarity to human skin. Nevertheless, it is still a challenging task to simultaneously prepare a self-healed and adhesive conductive hydrogel with good toughness, temperature tolerance and high sensing performance, especially with high sensitivity and a low detection limit. Herein, we developed a new strategy to improve the toughness and sensing performance of a multifunctional conductive hydrogel by simultaneously using dissolved chitosan (CS) and solid chitosan nanofibers (CSFs) to induce the formation of hierarchical polymeric networks in the hydrogel. The tensile strength and elongation at break of the hydrogel could be improved from 70.3 kPa and 1005 % to 173.9 kPa and 1477 %, respectively, simply by introducing CSFs to the hydrogel, and its self-healing, adhesive and antibacterial properties were effectively retained. When serving as a resistive sensing material, the introduction of CSFs increased the gauge factor of the hydrogel-based strain sensor from 8.25 to 14.27. Moreover, the hydrogel-based strain sensor showed an ultralow detection limit of 0.2 %, excellent durability and stability (1000 cycles) and could be used to detect various human activities. In addition, the hydrogel prepared by using a water-glycerol binary solvent system showed temperature-tolerant performance and possessed adequate sensitivity when serving as a resistive sensing material. Therefore, this work provides a new way to prepare multifunctional conductive hydrogels with good toughness, sensing performance and temperature tolerance to expand the application range of hydrogel-based strain sensors.


Assuntos
Quitosana , Nanofibras , Materiais Inteligentes , Humanos , Hidrogéis , Antibacterianos , Condutividade Elétrica , Íons
8.
Int J Biol Macromol ; 259(Pt 1): 129225, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38184053

RESUMO

Liquid metal (LM) microdroplets have garnered significant interest as conductive materials for initiating free radical polymerization in the development of conductive hydrogels suited for strain sensors. However, crafting multi-functional conductive hydrogels that boast both high stretchability and superior sensing capabilities remains as a challenge. In this study, we have successfully synthesized LM-based conductive hydrogels characterized by remarkable stretchability and sensing performance employing acrylic acid (AA) to evenly distribute chitosan nanofibers (CSFs) and to subsequently catalyze the free radical polymerization of AA. The resultant polymer network was crosslinked within situ polyacrylic acid (PAA), facilitated by Ga3+ in conjunction with guar gum (GG)-stabilized Ga droplets. The strategic interplay between the rigid, and protonated CSFs and the pliable PAA matrix, coupled with the ionic crosslinking of Ga3+, endows the resulting GG-Ga-CSF-PAA hydrogel with high stretchability (3700 %), ultrafast self-healing, robust moldability, and strong adhesiveness. When deployed as a strain sensing material, this hydrogel exhibits a high gauge factor (38.8), a minimal detection threshold, enduring durability, and a broad operational range. This versatility enables the hydrogel-based strain sensor to monitor a wide spectrum of human motions. Remarkably, the hydrogel maintains its stretchability and sensing efficacy under extreme temperatures after a simple glycerol solution treatment.


Assuntos
Acrilatos , Quitosana , Nanofibras , Humanos , Hidrogéis , Condutividade Elétrica , Radicais Livres
9.
Int J Biol Macromol ; 268(Pt 1): 131692, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38702247

RESUMO

Natural bioactive molecules such as phenolic acids and alkaloids play a crucial role in preserving the quality and safety of food products, particularly oils, by preventing oxidation. Berberis integerrima, a rich source of such antioxidants, has been explored in this study for its potential application in soybean oil preservation. Electrospun nanofibers, composed of polyvinyl alcohol and chitosan, were fabricated and loaded with an alcoholic extract of Berberis integerrima. The antioxidant activity of Berberis integerrima was evaluated, and the phenolic compounds contributing to its efficacy were identified and quantified. The physicochemical properties of the polyvinyl alcohol /chitosan/Berberis integerrima nanofibers, including morphology, crystallinity, functional groups, and thermal stability, were characterized. The results revealed that the polyvinyl alcohol/chitosan/Berberis integerrima nanofibers exhibited high antioxidant capacity and improved the stability of Berberis integerrima, indicating their potential as effective and biodegradable materials for food preservation. This study underscores the potential of harnessing natural antioxidants from Berberis integerrima in nanofibers to enhance the quality and safety of soybean oil.


Assuntos
Antioxidantes , Berberis , Quitosana , Nanofibras , Oxirredução , Óleo de Soja , Quitosana/química , Nanofibras/química , Óleo de Soja/química , Antioxidantes/química , Antioxidantes/farmacologia , Berberis/química , Álcool de Polivinil/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia
10.
Int J Biol Macromol ; 249: 126056, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37524280

RESUMO

The paper aimed to prepare quaternary chitosan-based nanofibers as bioabsorbable wound dressings. To this aim, fully biodegradable chitosan/N,N,N-trimethyl chitosan (TMC) nanofibers were designed and prepared via electrospinning, using poly(ethylene glycol) as sacrificial additive. The new biomaterials were structurally and morphologically characterized by FTIR and NMR spectroscopy, thermogravimetric analysis, X-ray diffraction and scanning electron microscopy, and their properties required for wound dressings application were investigated and discussed in detail. Thus, the nanofiber behavior was investigated by swelling, dynamic vapor sorption, and in vitro biodegradation in media mimicking the wound exudate. The mechanical properties were analysed from the stress-strain curves, the bioadhesivity from the texture analysis and the mucoadhesivity from the Zeta potential and transmittance measurements. The antimicrobial activity was assessed against S. aureus and E. coli strains, and the biocompatibility was tested in vitro on normal human dermal fibroblasts, and in vivo on rats. The application of the fiber mats with the best balance of properties as dressings on deep burn wound models in rats showed wound closure and active healing, with fully restoration of epithelia. It was concluded that the combination of chitosan with TMC into nanofibers provides new potential bioabsorbable wound dressing, opening new perspectives in regenerative medicine.


Assuntos
Quitosana , Nanofibras , Ratos , Humanos , Animais , Quitosana/química , Antibacterianos/farmacologia , Antibacterianos/química , Nanofibras/química , Staphylococcus aureus , Escherichia coli , Implantes Absorvíveis , Bandagens
11.
Polymers (Basel) ; 14(10)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35631977

RESUMO

A novel drug delivery system based on chitosan nanofibers containing some steroidal derivatives was developed using an electrospinning process. Oxazolines and aziridines from the cholestane series of steroidal epoxides were successfully synthesized and characterized by elemental analysis, Fourier transforms infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1HNMR), and mass spectroscopy (MS). Steroidal-compound-loaded chitosan (ST-CH) nanofibers were fabricated using the electrospinning technique in the presence of polyvinylpyrrolidone (CH/PVP). The electrospun nanofibers were characterized by scanning electron microscopy (SEM). The swelling degree of the electrospun nanofibers and their steroidal compound release performance were studied as well. Furthermore, their antibacterial activity against gram-positive (Staphylococcus aurous) and gram-negative bacteria (Escherichia coli) was evaluated. The experimental data revealed that identical and bead-free nanofiber mats loaded with 10 Wt. % of synthesized steroidal derivatives had been obtained. The FTIR spectrum proved that no change occurred in the chitosan structure during the electrospinning process. The synthesized nanofiber mats showed a high swelling degree and a burst release of steroidal compounds after 2 h doping in phosphate buffer saline. In addition, the electrospun nanofibers containing 3ß-chloro-N-amido-5α-cholestano-aziridine and those containing 3ß-acetoxy-N-amido-5α-cholestano-aziridine were the most active, with activity indices of 91 and 104% in the case of S. aureus and 52% and 61% in the case of E. coli, respectively. The release mechanism by CH/PVP of the drug samples was studied based on the charge density and diffusion controlled factors. The oxazoline derivatives release mechanism from CH/PVP was evaluated by applying the suppositions of the Ritger-Peppas kinetic model and by estimating the transport exponent; the latter revealed the involvement of the solvent diffusion and chain relaxation processes. Tailored steroidal loaded-chitosan (ST-CH) nanofibers are expected to be feasible and efficient drug delivery systems.

12.
Biomater Adv ; 137: 212871, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35929246

RESUMO

Biocompatible fibrous scaffolds based on highly deacetylated chitosan were fabricated using high-throughput solution blow spinning. Scanning electron microscopy analysis revealed that the chitosan nanofiber scaffolds had ultrafine and continuous fibers (300-1200 nm) with highly interconnected porous structures (30-75% porosity), mimicking some aspects of the native extracellular matrix in skin tissue. Post-treatment of as-spun nanofibers with aqueous potassium carbonate solution resulted in a fibrous scaffold with a high chitosan content that retained its fibrous structural integrity for cell culture. Analysis of the mechanical properties of the chitosan nanofiber scaffolds in both dry and wet conditions showed that their strength and durability were sufficient for wound dressing applications. Significantly, the wet scaffold underwent remarkable elastic deformation during stretch such that the elongation at break dramatically increased to up to 44% of its original length, showing wavy fiber morphology near the break site. The culture of normal human dermal fibroblast cells onto scaffolds for 1-14 days demonstrated that the scaffolds were highly compatible and a suitable platform for cell adhesion, viability, and proliferation. Secretion profiles of wound healing-related proteins to the cell culture medium demonstrated that chitosan fibers were a promising scaffold for wound healing applications. Overall, the dense fibrous network with high porosity of the chitosan nanofiber scaffold and their mechanical properties indicate that they could be used to design and fabricate new materials that mimic the epidermis layer of natural skin.


Assuntos
Quitosana , Nanofibras , Quitosana/química , Humanos , Nanofibras/química , Porosidade , Alicerces Teciduais/química , Cicatrização
13.
Int J Biol Macromol ; 212: 527-535, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35580746

RESUMO

Using electrospun chitosan/polyethylene oxide nanofibers mat (CS/PEO NFM) as carrier, Cu@CS/PEO NFM, a new tetracycline (TC) solid-state colorimetric sensor, were simply prepared by directly immobilizing Cu2+ on surface of CS/PEO NFM. After immersing in TC solutions, Cu@CS/PEO NFM can display visible color changes to the naked eye within 5.0 min, and the TC concentration-dependent color changes can also be quantitatively analyzed with a smartphone. Because Cu2+ can enhance the adsorption of CS/PEO NFM for TC, Cu@CS/PEO NFM possess a more sensitive response ability to TC, ensuring that the colorimetric sensing detection will not be interfered by other coexisting drugs. Due to the reversible combination of chitosan and Cu2+, the colorimetric sensing ability of Cu@CS/PEO NFM can be regenerated even after being reused at least 4 times. In addition, the naked eye detection limit of Cu@CS/PEO NFM-based colorimetric sensing is 65 µg kg-1, which does not exceed the maximum residue limit in milk samples set by China (100 µg kg-1). The obtained results fully indicated the practical application value of this method in preventing the hazard of TC residues.


Assuntos
Quitosana , Nanofibras , Antibacterianos/química , Quitosana/química , Colorimetria , Cobre , Nanofibras/química , Polietilenoglicóis/química , Tetraciclina
14.
Carbohydr Polym ; 298: 120101, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36241324

RESUMO

Polysaccharide materials, including bagasse cellulose nanocrystals (BCNCs), chitosan nanofibers (ChNFs), and sodium alginate (SA), were blended with oregano essential oil (OEO) to make single- and multi-polysaccharide edible coating suspensions. The prepared suspensions were spray-coated on strawberry surface to form thin films with thickness varying from about 570 to 790 nm for single-polysaccharide coatings and 690-930 nm for multi-polysaccharide coatings. The coatings made with multi-polysaccharide were more effective in inhibiting fungal growth compared with single-polysaccharide coatings. Strawberry treated with SA/BCNC/ChNF/OEO formulation had only 10.8 % weight loss after nine days of storage. In contrast, uncoated and single-polysaccharide coated strawberries had >37.0 % and 28.6 % weight loss, respectively. In addition, the SA/BCNC/ChNF/OEO coating retained desired moisture, respiration rate, stiffness, firmness, and appearance properties of strawberry due to its gas barrier properties resulting from the entangled matrix structure. These results suggest that the multi-polysaccharide suspensions with OEO have a high potential for application as edible coatings for retarding senescence of strawberries.


Assuntos
Quitosana , Fragaria , Nanoestruturas , Óleos Voláteis , Alginatos , Celulose/farmacologia , Quitosana/química , Quitosana/farmacologia , Conservação de Alimentos/métodos , Fragaria/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Redução de Peso
15.
Int J Biol Macromol ; 177: 100-110, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33539956

RESUMO

Electrospun hybrid nanofibers have been extensively regarded as drug carriers. This study tries to introduce a nano fibrous wound dressing as a new strategy for a topical drug-delivery system. The vancomycin (VCM)-loaded hybrid chitosan/poly ethylene oxide (CH/PEO) nanofibers were fabricated by the blend-electrospinning process. Morphological, mechanical, chemical, and biological properties of nanofibers were examined by SEM, FTIR, release profile study, tensile assay, Alamar Blue cytotoxicity evaluation, and antibacterial activity assay. In vivo wound healing activity of hybrid CH/PEO/VCM nanofibers was evaluated in full-thickness skin wounds of rats. The hybrid CH/PEO/VCM nanofibers were successfully fabricated in a nanometer. The CH/PEO/VCM 2.5% had higher Young's Modulus, better tensile strength, smaller fiber diameter with sustained-release profiles compared to CH/PEO/VCM 5%. All nanofibers did not show any significant cytotoxicity (P < 0.05) on the normal fibroblast cells. Also, VCM-load hybrid CH/PEO nanofibers successfully inhibited bacterial growth. The wound area in the rats treated with CH/PEO/VCM 2.5% was less than CH/PEO/VCM 5% treated group. According to histological evaluation, the CH/PEO/VCM 2.5% group showed the fastest wound healing than other treatment groups. Results of this study proposed that CH/PEO/VCM nanofibers could promote the wound healing process by reducing the side effects of VCM as a topical antimicrobial agent.


Assuntos
Quitosana/química , Óxido de Etileno/química , Nanofibras/química , Polietilenoglicóis/química , Vancomicina/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Bandagens , Modelos Animais de Doenças , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Vancomicina/química
16.
Int J Biol Macromol ; 183: 790-810, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33965480

RESUMO

In recent years, the incidence of cancer is increasing every day due to poor quality of life (industrialization of life). Therefore, the treatment of cancer has received much attention from therapists. So far, many anticancer drugs have been used to treat cancer patents. However, the direct use of the anticancer drugs has the adverse side effects for patents and several limitations to treat process. Natural chitosan nanofibers prepared by electrospinning method have unique properties such as high surface area, high porosity, suitable mechanical properties, nontoxicity, biocompatibility, biodegradability, biorenewable, low immunogenicity, better clinical functionality, analogue to extracellular model, and easy production in large scale. Therefore, this bio-polymer is a very suitable case to deliver of the anti-cancer drugs to treat cancer patents. In this review summarizes the electrospinning synthesis of chitosan and its therapeutic application for the various cancer treatment.


Assuntos
Antineoplásicos/uso terapêutico , Quitosana/química , Neoplasias/tratamento farmacológico , Antineoplásicos/química , Sistemas de Liberação de Medicamentos , Humanos , Nanofibras , Porosidade , Qualidade de Vida
17.
Int J Biol Macromol ; 193(Pt A): 996-1008, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34756969

RESUMO

Chitosan-based nanofibers (CS-NFs) are excellent artificial extracellular matrices (ECMs) due to the resemblance of CS with the glycosaminoglycans of the natural ECMs. Despite this excellent feature, the poor electrospinnability and mechanical properties of CS are responsible for important limitations in respect to its biomedical applications. To improve the CS's physico-chemical properties, new bioactive and biomimetic CS-NFs were formulated with polyethylene oxide (PEO), having incorporated different active components (ACs) with important beneficial effects for healing. Manuka honey (trophic and antimicrobial effects), propolis (antimicrobial effects), Calendula officinalis infusion (antioxidant effect, reepithelialization stimulating agent), insulin (trophic effect), and L-arginine (angiogenic effect) were selected as ACs. SEM morphology analysis revealed well-alignment, unidirectional arrays, with small diameters, no beads, and smooth surfaces for developed CS_PEO-ACs NFs. The developed NFs showed good biodegradability (NFs mats lost up to 60% of their initial weight in PBS), increased hemocompatibility (hemolytic index less than 4%), and a reduced cytotoxicity degree (cell viability degree more than 90%). In addition, significant antioxidant and antimicrobial effects were noted for the developed NFs which make them suitable for chronic wounds, due to the role of oxidative stress and infection risk in delaying normal wound healing. The most suitable for wound healing applications seems to be CS_PEO@P_C which showed an improved hemolysis index (2.92 ± 0.16%), is non-toxic (cell viability degree more than 97%), and has also significant radical scavenging effect (DPPH inhibition more than 65%). In addition, CS_PEO@P_C presents increased antimicrobial effects, more noticeably for Staphylococcus aureus strain, which is a key feature in preventing wound infection and delaying the healing process. It can be concluded that the developed CS/PEO-ACs NFs are very promising biomaterials for wound care, especially CS_PEO@P_C.


Assuntos
Bandagens , Materiais Biocompatíveis , Biomimética/métodos , Quitosana , Nanofibras/uso terapêutico , Polietilenoglicóis , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Quitosana/química , Quitosana/farmacologia , Humanos , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Cicatrização/efeitos dos fármacos
18.
Carbohydr Polym ; 254: 117465, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357924

RESUMO

Designing multifunctional surfaces is key to develop advanced materials for orthopedic applications. In this study, we design a double-layer coating, assembled onto the completely regular titania nanotubes (cRTNT) array. Benefiting from the biological and topological characteristics of chitosan nanofibers (CH) and reduced graphene oxide (RGO) through a unique assembly, the designed material features promoted osteoblast cell viability, prolonged antibiotic release profile, as well as inhibited bacterial biofilm formation. The synergistic effect of RGO and CH on the biological performance of the surface is investigatSed. The unique morphology of the nanofibers leads to the partial coverage of RGO-modified nanotubes, providing an opportunity to access the sublayer properties. Another merit of this coating lies in its morphological similarity to the extracellular matrix (ECM) to boost cellular performance. According to the results of this study, this platform holds promising advantages over the bare and bulk biopolymer-modified TNTs.


Assuntos
Quitosana/síntese química , Materiais Revestidos Biocompatíveis/química , Grafite/química , Nanocompostos/química , Osteoblastos/efeitos dos fármacos , Titânio/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Portadores de Fármacos , Liberação Controlada de Fármacos , Humanos , Cinética , Nanocompostos/ultraestrutura , Nanotubos/química , Nanotubos/ultraestrutura , Osteoblastos/citologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Vancomicina/farmacologia
19.
Int J Biol Macromol ; 167: 1176-1197, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33197477

RESUMO

Recent advancements in the synthesis, properties, and applications of chitosan as the second after cellulose available biopolymer in nature were discussed in this review. A general overview of processing and production procedures from A to Z was highlighted. Chitosan exists in three polymorphic forms which differ in degree of crystallinity (α, ß, and γ). Thus, the degree of deacetylation, crystallinity, surface area, and molecular mass significantly affect most applications. Otherwise, the synthesis of chitosan nanofibers is suffering from many drawbacks that were recently treated by co-electrospun with other polymers such as polyvinyl alcohol (PVA), polyethylene oxide (PEO), and polycaprolactone (PCL). Ultimately, this review focuses on the area of new trend utilization of chitosan nanoparticles as nanospheres and nanocapsules, in cartilage and bone regenerative medicine. Owing to its biocompatibility, bioavailability, biodegradability, and costless synthesis, chitosan is a promising biopolymeric structure for water remediation, drug delivery, antimicrobials, and tissue engineering.


Assuntos
Bioimpressão/métodos , Quitosana/química , Quitosana/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Nanocápsulas/química , Nanofibras/química , Nanopartículas/química , Engenharia Tecidual/métodos , Anti-Infecciosos/farmacologia , Materiais Biocompatíveis/química , Nanocápsulas/ultraestrutura , Nanopartículas/ultraestrutura , Solubilidade , Alicerces Teciduais/química
20.
Int J Biol Macromol ; 164: 1461-1474, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32735933

RESUMO

In the present study, the various zeolites including hydrophilic Y zeolite, hydrophobic ZSM-5 zeolite and metal organic frameworks (MOFs) including MIL-101 and ZIF-8 were incorporated into the PLGA/chitosan nanofibers for controlled release of Paclitaxel anticancer drug against prostate cancer in vitro and in vivo. The synthesized nanoparticles and nanofibers were characterized using FTIR, XRD, SEM, BET and water contact angle analysis. The drug loading efficiency of nanofibers containing zeolites and MOFs indicated that the MOFs were more useful compared with zeolites for higher loading of Paclitaxel molecules. The Paclitaxel release behavior from nanofibers containing zeolites and MOFs were also examined. The MTT assay and DAPI staining analysis were used to determine the cytotoxicity and apoptosis effect of nanofibers containing Paclitaxel against LNCaP prostate cancer cell lines. The tumor inhibition rate in vivo was carried out to obtain the optimum nanofibrous formulation with maximum cell death percentage and tumor inhibition rate. The obtained results revealed the better activity of MOFs compared nanozeolites for higher loading of Paclitaxel drug into the nanoparticles and a more sustained release of drug from nanofibers containing MOFs.


Assuntos
Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Paclitaxel/administração & dosagem , Neoplasias da Próstata/metabolismo , Antineoplásicos/administração & dosagem , Morte Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Quitosana/química , Humanos , Masculino , Estruturas Metalorgânicas/química , Microscopia Eletrônica de Varredura , Nanofibras/química , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Neoplasias da Próstata/tratamento farmacológico , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Zeolitas/química
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