The possibility of using fibrin-based collagen as an antibiotic delivery system

Collagen and fibrin are known to have potential use as a local drug-delivery system. This experimental study was designed to evaluate whether a fibrinogen-based collagen (FBC) fleece, coated with thrombin and aprotinin, can be used as an antibiotic delivery system. In an in vitro study, gentamicin, fosfomycin, ampicillin, ciprofloxacin and dibekacin were absorbed by the FBC, Kirby-Bauer disks (KBDs), and expanded polytetrafluoroethylene. After washing with saline or phosphate buffer saline (PBS) 3 times for 6, 12 and 24 h, each sample was analyzed for antibiotic retention. In an in vivo study, we implanted the FBC onto mouse livers and dripped gentamicin and ciprofloxacin onto the FBC. The FBCs were subsequently collected and analyzed for their antibiotic activities. After irrigation with saline, each antibiotic showed different activities. After PBS washing, the FBC impregnated with each antibiotic had higher activity than the KBDs, and inhibited the bacterial growth by 60-80 % compared to the control. Gentamicin dripped onto the FBC could inhibit bacterial growth after 48 h in vivo without affecting the hemostatic properties of the FBC. However, the FBC treated with ciprofloxacin exhibited antibacterial activity for only 3 h. Some bases, including FBC, can retain antibacterial activities dependent on the ingredients of the base and the type of antibiotic. Gentamicin, but not ciprofloxacin, was retained in the FBC in vivo. These results suggest that absorbent FBC might be useful not only as hemostatic material, but also as a local drug-delivery system.