Synthesis and in vitro stability of macromolecular prodrugs of norfloxacin

Oligopeptide derivatives of the antimicrobial drug norfloxacin, having the tetrapeptides gly-phe-ala-leu or gly-phe-leu-gly substituted on the piperazine amino group, were subsequently coupled with chloroformate-activated dextran. In vitro release experiments in aqueous buffer demonstrate the conjugates to be stable in buffers of pH 7.4 and 5.5. However, in the presence of lysosomal enzymes, the derivatives are degraded. The rate of degradation is followed by HPLC-analysis. (C) 1997 Elsevier Science Ireland Ltd.