Dresden 2006 – wissenschaftliches Programm
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CPP: Chemische Physik und Polymerphysik
CPP 12: POSTER Colloids, Nanoparticles and Self-Organizing Systems
CPP 12.6: Poster
Dienstag, 28. März 2006, 17:00–19:00, P3
Monitoring enzymatic degradation of polymeric nanoparticles with scattering methods — •Thomas Siegemund1,2, Bernd-Reiner Paulke3, Herbert Schmiedel1, Natalie Bordag2, Steffen Lindert1, and Wolfgang Härtig2 — 1Universität Leipzig, Institut für Experimentalphysik I, Physik der weichen Materie, Linnéstraße 5, 04103 Leipzig — 2Universität Leipzig, Paul-Flechsig-Institut für Hirnforschung, Jahnallee 59, 04109 Leipzig — 3Fraunhofer Institut für angewandte Polymerforschung, Geiselbergstraße 69, 14476 Potsdam
Nanoparticles can be used as carriers for the delivery of drugs. We prepared nanoparticles as carriers for the model drug thioflavin T that binds Alzheimer’s disease related fibrillar amyloid β-peptides in the brain. These polymer colloids are composed of a polystyrene core and a degradable poly(butyl-2-cyanoacrylate) shell with diameters from 60 to 170 nm. The enzymatic degradation of core-shell nanoparticles, as required in vivo, was observed after their treatment with porcine liver esterase, a non-specific esterase, and basic/acidic hydrolysis in vitro. Shells of nanoparticles were dose-dependently degraded while their polystyrene cores remained intact. We applied light scattering and neutron scattering as useful tools to monitor the particle diameters and to evaluate details of the degradation process, especially the degradation-dependent changes in the neutron scattering-length density profile. The degradation speed was studied at different temperatures as function of nanoparticle, enzyme and salt concentration at fixed pH. Deviations from Michaelis-Menten behavior are discussed within a simple model.