Activity of Antimicrobial Silver Polystyrene Nanocomposites

Abstract EN

A simple technique based on doping polymers with in situ generated silver nanoparticles (Ag/PS films) has been developed.

In particular, an antiseptic material has been prepared by dissolving silver 1,5-cyclooctadiene-hexafluoroacetylacetonate in amorphous polystyrene, and the obtained solid solution has been heated for ca.

10 s at a convenient temperature (180°C).

Under such conditions the metal precursor decomposes producing silver atoms that diffuse into the polymer and clusterize.

The antimicrobial characteristics of the resulting polystyrene-based material have been accurately evaluated toward Escherichia coli (E.

coli) comparing the cytotoxicity effect of 10 wt.% and 30 wt.% (drastic and mild annealing) silver-doped polystyrene to the corresponding pure micrometric silver powder.

Two different bacterial viability assays were performed in order to demonstrate the cytotoxic effect of Ag/PS films on cultured E.

coli: (1) turbidimetric determination of optical density; (2) BacLight fluorescence-based test.

Both methods have shown that silver-doped polystyrene (30 wt.%) provides higher antibacterial activity than pure Ag powder, under similar concentration and incubation conditions.