Ciprofloxacin-loaded polyisobutylcyanoacrylate nanoparticles: pharmacokinetics and in vitro antimicrobial activity

The disposition of ciprofloxacin in free form and loaded PIBCA/NP has been studied after intravenous infusion to the rabbit. Data from plasma concentration profiles revealed that pharmacokinetic parameters of ciprofloxacin associated with the colloidal carrier were greatly modified. Thus, ciprofloxacin-loaded PIBCA/NP led to increased AUG, t(1/2) and V-d, and to a decreased Cl as compared with drug in solution. This could be due not only to the colloidal drug carrier but also to the pharmacokinetics of ciprofloxacin itself. Studies of efficacy against Mycobacterium? avium complex in human macrophages proved that ciprofloxacin-loaded PIBCA/NP was more effective than free drug. The cytotoxicity of the polymeric material was observed at concentrations higher than 80 mu g of PIBCA per mi with drastic reduction of viable macrophages. This may explain why the efficacy of ciprofloxacin associated with nanoparticles was much lower than expected. (C) 1998 Elsevier Science B.V. All rights reserved.