Nanocrystals Enable Carrier-Free Drug Delivery

Buffalo, NY (Mar. 7)-Scientists at the University at Buffalo’s (www.buffalo.edu) Institute for Lasers, Photonics, and Biophotonics and Roswell Park Cancer Institute (RPCI, Buffalo, NY, www.roswellpark.org) have developed a drug-delivery system comprising 100-nm nanocrystals of pure HPPH, (2-devinyl-2-1’-hexyloxyethyl pyropheophorbide). The unique characteristic of the system is that it is carrier free, the drug itself acts as the carrier.

The hydrophobic, photosensitizer drug currently is undergoing Phase I–II human clinical trials at RPCI for the treatment of various cancers.

Research revealed that tumors effectively took up the nanocrystals in vivo, with results comparable to those of surfactant-based delivery models but without the toxicity that has been associated with those conventional systems. The study also showed that nanocrystals of the amphiphillic HPPH self-assembled in solution such that the clusters formed were not too big to settle to the bottom of the solution. The aggregation resulted in a controlled, colloidally stable suspension of nanosized crystals.

The research team plans to conduct additional in vivo trials and is considering the application of the delivery system to other hydrophobic drug compounds.