Polyaniline colloids stabilized with bioactive polysaccharides: Non-cytotoxic antibacterial materials.

Colloidal polyaniline dispersions stabilized with biocompatible polysaccharides, sodium hyaluronate and chitosan (both with two different molecular weights), were successfully formulated. The colloids were characterized by UV-vis spectra, particle-size distributions and morphology, as well as by their biological properties in terms of cytotoxicity and antibacterial activity. Colloids containing both chitosan and hyaluronate showed only mild cytotoxicities, which were mainly governed by the concentration of conducting polyaniline in the colloid. Antibacterial activity of the samples, however, depended both on the type of polysaccharide and the ratio between the stabilizer and polyaniline mass. The colloid synthetized using 0.2 M aniline hydrochloride, 0.1 M ammonium persulfate, and 1 wt.% sodium hyaluronate of molecular weight of 1.8-2.1 × 10 exhibited the highest antibacterial activity against both gram positive and gram negative bacteria. This formulation, therefore, allowed for the formation of potentially stimuli-responsive antibacterial colloidal particles with low cytotoxicity.