Stability of antibiotics bound to polytetrafluoroethylene with cationic surfactants.

This study evaluated the effect of prolonged storage and sterilization on the noncovalent bonding of penicillin to polytetrafluoroethylene grafts. The surfactant tridodecylmethylammonium chloride was unaffected by prolonged storage or sterilization, and its ability to bind penicillin remained constant for as long as 3 months. Steam or ethylene oxide sterilization markedly diminished the antibacterial activity of bound penicillin. However, the antibacterial properties of penicillin remained constant for up to 12 weeks when the grafts were stored at either 4 degrees C or room temperature. Thus, the bonding process appears to increase the stability of the antibiotic, and the data presented suggest that vascular prostheses can be treated with a surfactant, sterilized, and stored for at least 3 months. Grafts can then be treated with an antibiotic in the operating room, washed, and implanted.