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

A catheter surface was modified by coating a cellulose acetate polymer. Adh esion of Pseudomonas aeruginosa ATCC 27853 to the surface was investigated by exposing bacterial cultures to three treatments: polymer impregnated wit h 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 mug/ml and higher. Lectins alone at 10% also showed inhibition of bacterial attachment. Howev er, the best result was achieved against bacterial adhesion and growth on s urfaces using a combination of 100 mug Ag+/ml and a lectin coating as a sur face treatment. This surface treatment was also effective against both fres h culture and a two-week-old culture containing P. aeruginosa producing exo polymers. Our results suggest that Ag+ impregnation combined with a lectin coating warrants further investigation as a potential means of protecting c atheters.