(142e) Investigations of the Strengths of Elliptical Nanoparticles In Drug Delivery Application

Nanoparticles modified with bioactive motifs binding with specific proteins are becoming advanced drug carriers enabling targeted drug delivery. However, it is still challenging to enhance the mobility of nanoparticles in circulation, so the particles can quickly reach target sites.  Previous studies reported that microparticles with an elliptical shape presents the better targeting efficiency than spherical microparticles because of the enhanced mobility.  This important role of particle morphology can be extended to nanoparticles, but this hypothesis has not been examined to dates, because of the lack of technique to prepare nanoparticles with elliptical shape.  

This study therefore presents a new method to control the morphology of nanoparticles using polymers self-assembled to form vesicles. The poly(N-hydroxyethyl-DL-aspartamide) (PHEA) was modified with pedant alkyl chains and poly(ethylene glycol) molecules to tune the aspect ratio of the nanoparticle, as confirmed with electron microscope.  As expected, the resulting elliptical nanoparticles presented the higher diffusivity than the spherical ones.  The elliptical PHEA nanoparticles further modified with oligopeptides containing Arg-Gly-Asp (RGD) sequence exhibited the enhanced binding efficiency to target cells, because of the increase of association rate and decrease of dissociation rate, according to surface plasmon resonance (SPR) spectroscope.  Overall, this study serves to provide an invaluable biomedical tool to improve the efficiency of targeted delivery of a wide array of drug molecules.