Authors: J.H. Park, K.M. Huh, S.C. Lee, W-K Lee, T. Ooya and K. Park
Affilation: Purdue University, United States
Pages: 124 - 127
Keywords: nanoparticle, hydrotropic polymer, dendrimer, polymer complex
Novel nanoparticulate drug delivery systems have received increasing attention for delivery of poorly water-soluble drugs and proteins. We have developed a new type of polymer micelles bearing the hydrotropic core segment, e.g., poly(2-(4-vinylbenzyloxy)-N,N-diethylnicotinamide), that enables the hydrophobic drug, such as paclitaxel, to be solubilized and stabilized. These hydrotropic polymer micelles have a size in the range of 30-50 nm which increased to 100-120 nm after paclitaxel loading. The resulting micelles released paclitaxel in a controlled manner and showed high physical stability in aqueous media for several months. As an alternative method to hydrotropic polymeric micelles, we have prepared hydrotropic dendrimers (2-5 nm in diameter), composed of the ethylene glycol unit which has a hydrotropic property. The water solubility of paclitaxel was increased by 10,000-fold in the presence of such dendrimers, and the solubilized paclitaxel was released from the dendrimer system into the surrounding aqueous solution, in which the release rate was a function of the dendrimer generation. Nanoparticles specifically designed for protein delivery have also been developed based on physical interactions between two polymers in an aqueous solution. The nanosized particles were formed by simple mixing of two polymer solutions through which physical crosslinking occurs. Lysozyme, a model protein, was effectively encapsulated by a simple mixing process.