BACTERIAL ADHESION TO ORTHOPEDIC IMPLANT POLYMERS

The degradable polymers poly(orthoester) (POE), poly(L-lactic acid) (P LA), and the nondegradable polymers polysulfone (PSF), polyethylene (P E), and poly(ether ether ketone) (PEEK) were exposed to cultures of St aphylococcus epidermidis, Pseudomonas aeruginosa, or Escherichia coli. Bacteria washed and resuspended in phosphate buffered saline (PBS) ad hered to polymers in amounts nearly twice those of bacteria that were left in their growth medium, tryptic soy broth (TSB). In TSB, there wa s variation in adhesion from species to species, but no significant va riation from polymer to polymer within one species. In PBS there were significant differences in the amounts of bacteria adhering to the var ious polymers with the exception of S. epidermidis, which had similar adhesion to all polymers. As a whole, P. aeruginosa was the most adher ent while S. epidermidis was the least adherent. The estimated values of the free energy of adhesion (Delta F-adh) correlated with the amoun t of adherent P. aeruginosa. When POE, PLA, and PSF were exposed to hy aluronic acid (HA) before exposure to the bacteria, there was 50% more adhesion of E. coli and P. aeruginosa on POE and PLA. With respect to bacterial adhesion, the biodegradable polymers (POE and PLA) in gener al were not significantly different from the nondegradable polymers. ( C) 1996 John Wiley & Sons, Inc.