Membranas termossensíveis baseadas em redes poliméricas semi-interpenetrantes de Quitosana e Poli(N-isopropilacrilamida)

Abstract

The present study aims to develop thermosensitive membranes with an intelligent mechanism of adhesion/release and potent antimicrobial action for the treatment of wounds. The membranes were prepared by electrosynthesis of the thermosensitive hydrogel poly (N-isopropylacrylamide) (PNIPAm) in the presence of chitosan (CHI). The material obtained is constituted by a semi-interpenetrating polymer network (sIPN) of CHI and PNIPAm. The chitosan is a natural biopolymer with activity bactericidal, anti-inflammatory and healing action. The commercial chitosan used was previously characterized in terms of its average molar mass (0.9312 * 105 g mol-1) by viscosimetric method and degree of deacetylation (86.23%), through conductometric titration. The PNIPAm hydrogel was incorporated to CHI polymer chain by electrochemical method using cyclic voltammetry technique. The sIPN CHI-PNIPAm membrane obtained was characterized by Fourier Transform Infrared Spectroscopy using the Attenuated Total Reflectance (FTIR-ATR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). FTIR-ATR spectra confirmed the polymerization of PNIPAm in the presence of CHI. TGA curve showed that sIPN membrane obtained has a composition of 33% chitosan and 55% PNIPAm. DSC thermal analysis showed a lower Tg of sIPN CHI-PNIPAm membrane compared to Tg of PNIPAm hydrogel. The phase transition temperature (LCST) of the sIPN CHI-PNIPAm membrane was determined by Ultaviolet-visible spectroscopy (UV-vis) the value found was 32 ° C.

Chitosan as an Outstanding Polysaccharide Improving Health-Commodities of Humans and Environmental Protection

“…Hence, thermosensitive nanocarriers containing chitosan have been designed for cancer therapy. For that, chitosan grafted with poly( N -vinylcaprolactam) or poly( N -isopropylacrylamide) are the most-used copolymers in trials where the temperature is a triggering factor for drug release [ 62 , 63 ]; this responsiveness is derived from a reversible phase transition based on their lower critical solution temperature (LCST). Additionally, dual- and triple-stimuli responsive materials are created for achieving a targeted and controlled drug release.…”

Fungal chitosan as membranous material modified by atmospheric plasma

“…For additional analysis, we suggested in vitro tests with the membranous to confirm its antimicrobial potential, cellular regeneration and cellular adhesion as described by literature for different membranous of chitosan (Braga et al, 2019;Rosendo et l., 2020).…”

Estudo sobre a utilização de polianidrido como abordagem terapêutica para o tratamento de lesões no tecido ósseo

“…Tendo o conhecimento dessas limitações, iniciou-se a busca por novas alternativas que levaram ao desenvolvimento de substitutos do enxerto ósseo sintético, em geral os substitutos ósseos são matérias naturais, sintéticos ou compostos usados para preencher defeitos ósseos para a promoção da consolidação do osso (Ogueri et al, 2019). A engenharia de tecidos necessita de uma sintese de novas substâncias que possuem propriedades que vão agir como um regenerador de tecido e como um dispositivo de liberação controlada de fármaco, o uso desse tipo de biomaterial deve possuir biocompatibilidade para aplicação ortopédica, mas para isso tem que possuir uma estrutura porosa para promover o crescimento celular e reparar, restaurar ou regenerar o tecido ósseo danificado (Braga, Flauzino Junior, González, & Queiroz, 2019;Brown & Laurencin, 2019).…”