Protection of catheter surfaces from adhesion of Pseudomonas aeruginosa by a combination of silver ions and lectins

Abstract

A catheter surface was modified by coating a cellulose acetate polymer. Adhesion of Pseudomonas aeruginosa ATCC 27853 to the surface was investigated by exposing bacterial cultures to three treatments: polymer impregnated with silver ions (Ag+), polymer surfaces coated with lectins and a combination of Ag+ and a lectin coating. The effective concentration of Ag+ providing protection against bacterial biofilm development was 100 μg/ml and higher. Lectins alone at 10% also showed inhibition of bacterial attachment. However, the best result was achieved against bacterial adhesion and growth on surfaces using a combination of 100 μg Ag+/ml and a lectin coating as a surface treatment. This surface treatment was also effective against both fresh culture and a two-week-old culture containing P. aeruginosa producing exopolymers. Our results suggest that Ag+ impregnation combined with a lectin coating warrants further investigation as a potential means of protecting catheters.