Abstract
Nanomedicine, defined as nanotechnology applied to health, is a rapidly increasing research area. Nanosized particles and capsules will play a central role in the development of future medication. Encapsulation of drugs will allow for the application of more protein- and gene-based medicine than today and hopefully for more non-invasive administration of these drugs. Surface modification of the capsules is expected to lead to more precise and targeted medication in the future. There are numerous methods available for producing nanocapsules. Among them, the miniemulsion process is very promising as it is an easy, direct and low cost method, which provides nanocapsules typically in the size range of 50-500 nm. It also allows the direct introduction of functional groups at the capsule surface during the preparation process.In the presented study the miniemulsion polymerization technique was applied to prepare nanocapsules of the biodegradable polymer poly(butyl-2-cyanoacrylate) (PBCA) with a size of approximately 200 nm and loaded with fluorescent dye. The encapsulation of model cancer drugs is in progress. For use in medical application as drug delivery system, an active and functional interface is necessary. The surface characteristic of the nanocapsules is crucial to avoid clearance by the reticuloendothelial system. Therefore, to prevent the uptake by monocytes and unspecific binding to cells, nanocapsules having poly(ethylene glycol) chains at the surface have been synthesized. Proliferation measurements with B-LCL cells confirmed that the nanocapsules are non-toxic at concentrations lower than 5•107 particles/ml. To achieve an active targeting interface, the antibody CD34 was coupled to the surface of the nanocapsules. Unexpected phenomena during antibody immobilization will be presented and possible explanations discussed. Capsule improvements by several routes are under investigation and initial experiments are promising. Unspecific binding to cells and the targ
