POLY(LACTIDE-CO-GLYCOLIDE) COMPOSITES CONTAINING ANTIBACTERIAL SILVER NANOPARTICLES - IN VITRO PRELIMINARY STUDY

This work concerns the biological and morphological assessment of poly(lactide-co-glycolide)/silver nanoparticle (nAg) composites prepared by the slip-casting method. Due to the significance of the bactericidal properties of such materials, antibacterial activity against Gram-positive - Staphylococcus aureus and Gram-negative - Escherichia coli was evaluated by means of the surface deposition method. By inductively coupled plasma mass spectrometry (ICP-MS), it was possible to evaluate the amount of released silver ions and to determine their impact on the surrounding environment of bacteria. The material microstructure and dispersion of the modifier phase were estimated by using electron scanning microscopy with elemental analysis in micro-areas (SEM+EDS). The roughness and Theta angle measurements allowed us to define the surface character of the investigated materials. The tests of antibacterial efficacy proved that nanosilver-modified composites have bactericidal activity against the tested bacteria. The antibacterial efficacy of the tested materials depends on the amount of modifier phase (nAg). Along with an increasing volume fraction of modification phase, a different degree of the homogenization process was observed as well as a reduction in composite homogenization, a roughness increase and Theta angle decrease. At the same time, the composites showed higher wettability. Spectrometric analysis showed that the amount of released silver ions depends on the amount of nanoparticles present in the polymer matrix.