We have developed a biodegradable, biocompatible system for the delivery of the antituberculotic antibiotic rifampicin with a built-in drug release and nanoparticle degradation fluorescence sensor. Polymer nanoparticles based on poly(ethylene oxide) monomethyl ether-block-poly(ε-caprolactone) were noncovalently loaded with rifampicin, a combination that, to best of our knowledge, was not previously described in the literature, which showed significant benefits. The nanoparticles contain a Förster resonance energy transfer (FRET) system that allows real-time assessment of drug release not only in vitro, but also in living macrophages where the mycobacteria typically reside as hard-to-kill intracellular parasites. The fluorophore also enables in situ monitoring of the enzymatic nanoparticle degradation in the macrophages. We show that the nanoparticles are efficiently taken up by macrophages, where they are very quickly associated with the lysosomal compartment. After drug release, the nanoparticles in the cmacrophages are enzymatically degraded, with half-life 88±11 min.

Department of Chemistry University of Oslo P O Box 1033 Blindern Oslo Norway

Department of Medical Microbiology 2nd Faculty of Medicine Charles University Prague and Motol University Hospital Prague Czech Republic

Institute of Cellular Biology and Pathology Charles University Prague 1st Faculty of Medicine Prague Czech Republic

Institute of Macromolecular Chemistry AS CR v v i Heyrovsky sq 2 Prague Czech Republic

References provided by Crossref.org

Effect of Nanoparticle Weight on the Cellular Uptake and Drug Delivery Potential of PLGA Nanoparticles

Selectively Biodegradable Polyesters: Nature-Inspired Construction Materials for Future Biomedical Applications