Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (08): 2274-2280.doi: 10.3866/PKU.WHXB20100807

• PHOTOCHEMISTRY AND SPECTROSCOPY • Previous Articles     Next Articles

Preparation and Spectroscopic Properties of Covalent Albumin Conjugates of Zinc Phthalocyanines Tetrasubstituted with Carboxyl Moieties

XIAO Rong-Ping, KE Mei-Rong, HUANG Jian-Dong, ZHANG Han-Hui   

  1. School of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350108, P. R. China
  • Received:2010-02-19 Revised:2010-04-08 Published:2010-07-23
  • Contact: HUANG Jian-Dong, ZHANG Han-Hui E-mail:jdhuang@fzu.edu.cn; hhzhang@fzu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20872016), Natural Science Foundation of Fujian Province, China (C0710033) and Program for New Century Excellent Talents in Fujian Province University, China (XSJRC2007-18).

Abstract:

A series of covalently bound albumin (bovine serum albumin (BSA) and human serum albumin (HSA)) conjugates of phthalocyanines functionalized with carboxyls were prepared and resulted in amide bonds. The phthalocyanines are tetra-α-(4-carboxyl phenoxy) phthalocyanine zinc (1) and tetra-α-[4-(2-carboxyl-ethyl) phenoxy] phthalocyanine zinc (3) as well as their corresponding tetra-β-substituted counterparts (compounds 2 and 4). The spectroscopic properties of these phthalocyanines and their bioconjugates in phosphate buffer saline solution (PBS) were investigated. The phthalocyanines that are covalently bound to the albumins have a more obvious monomeric absorption characteristic than the corresponding free phthalocyanines. Moreover, the spectroscopic characteristics of the phthalocyanines in the bioconjugates are not affected by solution pH. The substitution position of the carboxyl moieties on the phthalocyanine ring has an effect on the spectroscopic transformation of these macromolecules after conjugation with the albumins. Substitution at the α-position of the phthalocyanine ring leads to more prominent spectroscopic changes than that at the β-position. Both 1-albumin and 3-albumin in PBS show monomeric phthalocyanine spectra with Q-band maxima at about 697 nm and 706 nm, respectively.

Key words: Phthalocyanine, Albumin, Covalent conjugate, Spectroscopic property, Photosensitizer

MSC2000: 

  • O644