Fabrication of nonspherical particles for gene delivery remains a major challenge. In this study, novel rod-like nanoparticles are prepared for efficient gene delivery by self-assembly of alpha-cyclodextrin (alpha-CD) and polyethylenimine-methoxy poly(ethylene glycol) (PEI-mPEG).

The study reveals that the rod-like PEI-mPEG/alpha-CD particles can bind DNA effectively and the resulting PEIm-PEG/alpha-CD/DNA complexes show over four times higher gene delivery capability than their spherical counterparts and PEI(25K) due to more efficient cellular uptake.

Furthermore, the cytotoxicity of rod-like PEI-mPEG/alpha-CD is about five times lower than that of the nanospheres, and 50 times lower than that of DNA/PEI(25K). These results indicate that shape is an important parameter for the design of gene delivery vectors.