Investigation of polymer/lamellar silicate (PVP/bentonite) in the synthesis of modified release silver nanoparticle membranes
polymer; clay; silver nanoparticle
In view of the increasing resistance of microorganisms to antimicrobials, silver nanoparticles (NPAg) emerge as an effective alternative for the treatment of various health-related problems, given their high antimicrobial activity. Its placement through polymeric membranes with curative purposes has been highlighted by the possibility of using biocompatible polymers, among these, polyvinylpyrrolidone (PVP) stands out for acting in the NPAg synthesis process and preventing the formation of agglomerates. In this context, the addition of a polymer to a layered nanostructured clay, such as bentonite (Bt), forming a so-called lamellar silicate polymer (PSL) nanocomposite, constitutes an interesting material for study, given the ability to release sustained actives already described. in literature. Thus, the objective of this work is to synthesize and characterize the PVP/Bt/NPAg nanocomposite, evaluate its release and antimicrobial activity. The synthesis of the nanoparticles was performed using PVP as a silver reducing agent and as a stabilizer. The colloidal suspension was characterized by UV-Vis spectrophotometry, dynamic light scattering and zeta potential. After that, there was addition of bentonite in different proportions and interference in membrane formation was verified. Once the material was obtained, it went on to physicochemical characterization using X-ray diffraction (XRD), infrared spectroscopy (FTIV), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy. (EDS). The colloidal suspension was obtained and showed stability and a slow silver reduction aspect by PVP. The membranes produced showed, through XRD, that there was formation of the PSL nanocomposite and the amorphous characteristic of the polymer, crystalline of silver and bentonite, which was in its exfoliated mode. The FTIV indicated the participation of groups containing oxygen and nitrogen, from PVP, in the reduction of silver. The surface morphology of the samples was altered with the addition of bentonite, presented in flakes, and nanosilver, which exhibited a shiny appearance. The composition was confirmed by EDS without showing contamination peaks in the material. Thus, it is legitimate to continue the study with evaluation of the release of NPAg from the nanocomposite and the antimicrobial activity. Thus, it is expected that there will be formation of a modified release membrane for application as a dressing.