An isothiocyanato-functionalized phthalocyanine (Pc) was synthesized in good yield from the corresponding amine-substituted Pc. This Pc reacted with ethanolamine, biotin hydrazine, and biotin diethylamine under mild conditions (room temperature in DMF or DMSO in the presence of TEA) to produce the corresponding thiourea products in 60-75% yields. All Pcs showed intense Q absorptions in DMF around 677 nm, emissions centered at 683 nm, and fluorescence quantum yields in the range 0.18-0.27. The Pcs were phototoxic to human carcinoma HEp2 cells (IC50 similar to 7 at 1.5 J/cm(2)) and localized in multiple organelles, including the lysosomes, Golgi and ER. One biotin-Pc conjugate was injected via tail vein into nude mice bearing HT-29 tumors and demonstrated selective localization in the tumor tissue.
Publication Source (Journal or Book title)
JOURNAL OF PORPHYRINS AND PHTHALOCYANINES
Vicente, M. Graca H.; Okoth, Elizabeth A.; Zhou, Zehua; and Ongarora, Benson, "Synthesis and investigation of phthalocyanine-biotin conjugates" (2019). Faculty Publications. 34.