Antimicrobial activity of different wound dressing products treated with silver

The main goal of this work was to optimize the method of processing wound dressing products (like gauzes, sanitary pads, cotton wool, compresses, and bandages) with a commercial silver colloidal solution (Koloid doo, Belgrade, Serbia) and then to examine the antimicrobial properties of the obtained items in order to potentially reach the market with new improved wound dressing products. The influence of different silver concentrations used for treatment on antimicrobial activity was investigated only against Escherichia coli. The antimicrobial activity of different types of materials treated with silver solutions of 30 ppm was investigated against Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, Gram-positive bacteria Staphylococcus aureus, Bacillus subtilis, and Enterococcus faecalis, as well as the fungus Candida albicans. The microbial reduction of the tested materials loaded with a silver solution of 30 ppm (15-20 ?g of Ag on 1 g of fabric) against the Gram-negative bacteria E. coli and P. aeruginosa was almost maximal after 2 h of contact (i.e. 95 and 99 %, respectively). In the case of Gram-positive bacteria S. aureus, B. subtilis, and E. faecalis, a longer time is needed to completely eradicate bacteria (over 99 %). Antifungal activity testing against the fungus C. albicans gave moderate antifungal activity results.