Antibacterial polymeric nanocomposites synthesized by in-situ photoreduction of silver ions without additives inside biocompatible hydrogel matrices based on N-isopropylacrylamide and derivatives

MONERRIS, M.; BROGLIA, M.; YSLAS, I.; BARBERO, C.; RIVAROLA, C.

EXPRESS POLYMER LETTERS

BUDAPEST UNIV TECHNOL & ECON

Año: 2017 vol. 11 p. 946 - 962

1788-618X

Synthesis of antibacterial nanocomposite obtained by in-situ photoreduction of Ag+ ions impregnated inside abiocompatible hydrogel matrix is described. Hydrogel matrixes based on N-isopropylacrylamide (PNIPAM) and copolymersare synthesized by free radical polymerization in aqueous medium. The hydrogels are loaded with Ag+ ions and then silvernanoparticles (Ag-NPs) are obtained in-situ by application of UV light without using additives. Ag-NPs formation insidehydrogels is confirmed by UV?visible spectroscopy, scanning electronic microscopy (SEM) and transmission electronic microscopy(TEM). An extensive characterization of nanocomposites is performed by determining the partition coefficient ofAg+ ions before photoreduction, the Ag-NPs mass loaded per gram of hydrogel as a function of irradiation time, swellingcapacity and volume phase transition temperature. Fourier Transform Infrared (FTIR) spectra indicate the loss of some functionalgroups of the polymer backbone during reduction of Ag+ ions whereas 13C NMR spectra do not show any change inthe main carbon chain. Nanocomposites show antibacterial activity against Pseudomonas aeruginosas by release of Ag+ions while Ag-NPs remain inside matrix. Reducing/stabilizing character of hydrogel and antibacterial activity of nanocompositedepend on the chemical composition of the matrix.