RESUMO
The interactions of the new photosensitizer {2, 3, 9, 10, 16, 17, 23, 24-octakis[(3,5-dicarboxy)phenoxy]-phthalocyaninato}zinc(II) [ZnPc(COOH)16] and serum albumins (BSA and HSA) were investigated by absorption and fluorescence spectroscopy. The binding constants were found to be 2.25-2.94 x 10(6) L x mol(-1). The 1 : 1 ZnPc (COOH)16-BSA and ZnPc (COOH)16-BSA conjugates were also prepared by incubating a mixture of ZnPc(COOH)16 and the corresponding serum albumin in 2 : 1 mole ratio followed by separation by gel permeation chromatography. The Q band absorption and fluorescence emission of ZnPc(COOH)16 are slightly red-shifted in the conjugates, and the spectral features suggest that the phthalocyanine exists predominantly in monomeric form in the conjugates.
