Thrombin-sensitive peptide linkers for biological signal-responsive drug release systems.

We have previously reported an elevation of thrombin-like activity in infected wound exudates. Therefore, using this enzymatic activity as a biological signal, a system which can release an antimicrobial drug at infected wounds was investigated. In this paper, we report thrombin-sensitive peptide linkers, the key component of this system. Starting from amino acid sequences of the cleavage site in fibrinogen, which is the substrate of thrombin, we synthesized some thrombin-sensitive peptide linkers. We constructed devices in which the thrombin-sensitive peptide linker interconnected between polyvinyl alcohol hydrogel and gentamicin. The device was able to release gentamicin in response to thrombin.