Atividade antibacteriana de biomembranas à base de galactomanana da Fava Danta incorporadas com clorexidina

Abstract

The manufacture and use of biodegradable biomembranes from polysaccharides for an incorporation of bioactive drugs or molecules has aroused the industry interest in the manufacture of dressings used in wounds and sutures. These incorporated substances may play a cleaning role, or indirectly as an antimicrobial in the prevention/treatment of infections, in order to obtain better therapeutic results when compared to traditional passive dressings, such as gauze and cotton dressings. Among these polysaccharides, galactomannans stand out because of the property of forming films/membranes; however, the polysaccharides are water soluble and need to have their own better physical conditions according to their applicability. In order to this, crosslinked between polymer chains can be performed to improve such properties. With is the current developing challenge of new biodegradable matrices for an asset incorporation, this work objective to make biomembranes of galactomannan extracted from D. gardneriana seeds crosslinked with EDC and incorporated with chlorhexidine for application as antimicrobial dressings. Four types of biomembranes were developed: a non-crosslinked polysaccharide biomembrane, called a biomembrane control (BC), a reticulated biomembrane (BR) and biomembranes by two crosslinking way and incorporation of chlorhexidine (R1 and R2). Characterization by FTIR showed the presence of bands between 1560 and 1490 cm-1

, characteristics of functional groups of chlorhexidine in the spectra of biomembranes R1 and R2. The characterization by TGA/DTG demonstrated better thermal stability of BR and R2 in relation to BC. The crosslinked biomembranes (BR, R1 and R2) showed insolubility for 24 hours when immersed in water compared to uncrosslinked (BC) that lost its integrity in aqueous medium. In addition, an atomic force microscopy was performed to analyze the morphology of the biomembranes and to calculate the average roughness that varied from 1.83nm to 2.38nm. The biomembranes incorporated with chlorhexidine (R1 and R2) presented antimicrobial activity against bacteria of the genus Staphylococcus (with different susceptibility profiles) and Escherichia coli.