RESUMO
The incorporation of drugs in nanocomposites can be considered a potential strategy for controlled drug release. In this study, a nanocomposite based on bacterial cellulose and the palygorskite clay (BC/PLG) was produced and loaded with metronidazole (MTZ). The samples were characterized using X-ray diffraction (XRD) Spectroscopy, thermal analysis (TG/DTG) and Scanning Electron Microscopy (SEM). The barrier properties were determined to water vapor permeability (WVP). Adsorption tests with PLG were performed using MTZ and drug release profile of the membranes was investigated. The results indicated that PLG increased the crystallinity of the nanocomposites, and greater thermal stability when PLG concentration was 15.0% (BC/PLG15) was observed. WVP of the samples also varied, according to the clay content. Adsorption equilibrium was achieved from 400 mg/L of the PLG and a plateau in the MTZ release rates from BC/PLG was observed after 30 min. Therefore, the results of this study show the potential of these nanocomposite membranes as a platform for controlled drug release.
Assuntos
Celulose/química , Compostos de Magnésio/química , Metronidazol/farmacologia , Nanocompostos/química , Compostos de Silício/química , Adsorção , Cristalização , Preparações de Ação Retardada/farmacologia , Liberação Controlada de Fármacos , Nanocompostos/ultraestrutura , Permeabilidade , Vapor , Termogravimetria , Difração de Raios XRESUMO
Biopolymeric blends based on bacterial cellulose (BC) films modified with low molecular weight chitosan (Chi) were developed for controlled release of ciprofloxacin (Cip). Biophysical studies revealed a compatible and cooperative network between BC and Chi including deep structural changes in the BC matrix shown by spectroscopic and thermal analyses (SEM, roughness analysis, FTIR, XRD, TGA, mechanical properties and water vapor transmission rate). Incorporation of chitosan to BC matrix generated a thickening scaffold with high permeability to water vapor from 0.7 to 3.2 g mm/m2 h. Cip loaded onto the BC-Chi film showed a hyperbolic release profile with a 30% decrease in antibiotic release mediated by the presence of Chi. BC-Chi blend films containing Cip tested against Pseudomonas aeruginosa and Staphylococcus aureus showed a synergic effect of chitosan on Cip antimicrobial activity. Besides, in vitro studies revealed the lack of cytotoxicity of BC-Chi-Cip films in human fibroblasts.
Assuntos
Anti-Infecciosos/química , Bandagens , Celulose/química , Quitosana/química , Ciprofloxacina/química , Fibroblastos/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Linhagem Celular , Ciprofloxacina/farmacologia , Fibroblastos/metabolismo , Temperatura Alta , Humanos , Peso Molecular , Permeabilidade , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , TermogravimetriaRESUMO
BACKGROUND: Bacterial cellulose (BC) is a versatile material produced by microorganisms in the form of a membranous hydrogel, totally biocompatible, and endowed with high mechanical strength. Its high water-holding capacity based on its highly porous nanofibrillar structure allows BC to incorporate and to release substances very fast, thus being suitable for the preparation of skincare masks. AIMS: The preparation and characterization of cosmetic masks based on BC membranes and active cosmetics. METHODS: The masks were prepared by the simple incorporation of the cosmetic actives into BC membranes, used as a swelling matrix. The masks were characterized by Fourier transform infrared (FTIR), scanning electron microscopy (SEM), sensory tests, and skin moisture tests on volunteers. RESULTS: The results of sensory tests revealed the good performance of BC, being considered effective by the panel of volunteers, specially for adhesion to the skin (7.7 at the score scale), and improvement of the skin moisture (the hydration effect increased 76% in 75% of the volunteers that used vegetable extract mask formulation [VEM]), or a decrease in skin hydration (80% of the volunteers showed 32.6% decrease on skin hydration using propolis extract formulation [PEM] treatment), indicating the BC nanofiber membranes can be used to skincare applications. CONCLUSION: The results demonstrate the BC can be used as an alternative support for cosmetic actives for skin treatment.