Susceptibility of Biofilm Propagation by Pseudomonas aeruginosa and Staphylococcus epidermidis on Titanium-Boron Prosthetic Biometals

QUIJANO, J.A., ALAS, S., MARZANO, S. AND BRELLES-MARIÑO, G.

Carolina del Norte, Estados Unidos de America

Congreso; Annual Biomedical Research Conference for Minority Students (ABRCMS); 2010

American Society for Microbiology

Human prosthetics are being utilized more frequently as the populations that require their use expand. These cohorts include an increasing elderly population, American soldiers returning with war injuries, and members of the general public who suffer serious injury from accidents. The development of modern human prosthetics has resulted in more biocompatible implants, but they lack longevity due to prosthetic loosening that is caused by metal corrosion or chronic infection. One major area of concern is the formation of a biofilm on the prosthetic surface during infections. Using Pseudomonas aeruginosa, a bacterium that commonly produces biofilms in patient implants, we investigated the biocompatibility of novel titanium alloys with regard to their susceptibility to biofilm propagation. We examined stainless steel (SS), commercially pure titanium (CPTi), Ti-6Al-4V (Ti64) and three novel titanium alloys that contained varying percentage of boron. To determine the amount of biofilm growth, we performed crystal violet staining. Ideal growth conditions were obtained using flasks with 50mL of TSB media for 24 hours at 37˚C or using a biofilm reactor with 350mL TSB media, and allowing incubation for 48 hours at 37˚C. Preliminary results show that the Ti64 alloy permits less biofilm formation than SS and CPTi in culture flask conditions by P. aeruginosa, using crystal violet staining. Additionally, using the biofilm reactor, we determined that P. aeruginosa resulted in less biofilm formation on Ti64 than SS, CPTi, and the remaining alloys tested. In order to characterize the viability of the cells comprising the biofilm, we used the LIVE/DEAD® BacLight™ Bacterial Viability Kit and fluorescent microscopy. We determined that the biofilm contained a large percentage of dead cells. However, more analysis must be done to quantify biofilm viability grown on the various novel alloys, as this is an indicator of prosthetic longevity. At this stage, data indicate that the Ti-6Al-4V alloy may allow less biofilm formation than traditional metals and, thus, may be a better alternative to stainless steel and pure titanium as a prosthetic biometal.