Comparative investigation of drug delivery of collagen implants saturated in antibiotic solutions and a sponge containing gentamicin.

Collagen implants of various structures and a gelatine sponge were placed in five different antibiotic solutions until complete saturation occurred. The antibiotics were chosen to represent different drug classes (gentamicin sulphate, cefotaxim, fusidic acid, clindamycin, vancomycin). The collagen implants saturated with antibiotic solution and a lyophilized collagen sponge containing gentamicin sulphate were eluated in 0.066 M phosphate buffer (pH = 7.4) at 37 degrees C. The total eluation period is 7 d with buffer changes every 24 h. The antibiotic delivery by the collagen implants and the lyophilized sponge containing gentamicin sulphate is complete after a maximum of 4 d. If an implant that has a protective effect against wound infections over a period of 24-48 h is required, the materials described here are suitable. However, where treatment in infected areas should ensure antibiotic cover for 5-10 d, neither collagen materials immersed in antibiotic solutions nor collagen sponges containing gentamicin are suitable.