[A novel gemcitabine delivery system]

Indocyanine green (ICG) is specifically excreted through the biliary tracts. The authors applied ICG as a carrier of gemcitabine (GEM) to devising a novel drug delivery system. Our newly devised chitin flakes, ICG and GEM were mixed together. Then physiological saline solution was added to the mixture to form the system. The release profiles of GEM and ICG from the system were examined at various times in vitro. Anticancer activities of the GEM and ICG delivered from the system were detected by MTT assay method using human pancreatic cancer cell lines. The novel system was visco-elastic green sol at room temperature and changed to gel at body temperature. Seventy to 80% of GEM was gradually delivered from the system in 24 hours, and 30 to 50% of ICG was slowly released over 24 hours. The released GEM favorably demonstrated anticancer activities against the cancer cells, while the ICG released from the system showed no oncolytic activities. These suggested that our devised system would be clinically useful as a novel tool in cancer chemotherapy.