Biossíntese e caracterização de nanocelulose bacteriana para engenharia de tecidos

Abstract

Burns cause lesions of the epithelial lining, from an external agent, and can range from a small injury to more severe forms, capable of triggering systemic responses. The use of dressings containing healing and antimi-crobial substances are options for local therapy. Bacterial nanocellulose (BNC) dressings have already demonstrated their great potential due to their properties such as high purity, high water absorption capacity and optimum biological adaptability. The incorporation of metals in the nanocellulose membrane is quite promising. Silver nanoparticles (AgNPs) have been studied because of their antibacterial properties; cerium nitrate, Ce(NO3)3, on the other hand, increases the efficacy of the treatment because of its immunomodulato-ry properties. The objective of this work was to synthesize and characterize bacterial nanocellulose mem-branes functionalized with cerium nitrate and silver nanoparticles aiming the treatment of human skin that has been subject to burning injuries. Thermal behavior, interactions between BNC, Ce(NO3)3 and AgNP, as well as morphology, water retention capacity, rehydration capacity and antimicrobial potential were analyzed by thermogravimetry (TGA), scanning electron microscopy (SEM), analysis of water content, rehydration capacity and antimicrobial activity. Membranes formed by incorporation of Ce(NO3)3 and AgNPs simultane-ously, and submitted to heat treatment, preserved thermal properties of both materials, as well as a good rehydration capacity and a microbial reduction potential of 98% for Staphylococcus aureus. SEM analysis showed changes in morphology, pore size reduction and the presence of particles, what suggest successful incorporation of the compounds.