Synthesis And Properties Of Zinc Phthalocyanine Photosensitizer For Carboxylic Acid

Photodynamic therapy (PDT) is a new method for tumor therapy. Phthalocyanine (Pc) is a very promising kind of photosensitive drug, but they still exist some problems, such as low solubility and high aggregation. Low solubility has strong influence on their intravenously, and the anti-cancer activity can be significantly reduce by high aggregation of Pc in physiological environment. The solubility, aggregation and photosensitivity properties of Pc were closely related to kinds and numbers of the substituent on the side chain of them.In this paper, the ZnPcs substituted with different kinds and numbers of substituents have been synthesized, the relations between the kinds and numbers of substituents and the solubility, aggregation properties and photosensitive activity of Pcs have been studied, providing valuable references for the design of Pcs with high photosensitive activity, superior watersolubility and low aggregation. The main conclusions were as follows:1. The ZnPc derivatives substituted with hydroxy, amino and carboxyl have been syntheised. All of the above compounds were characterized with IR spectra, UV-Vis spectra,1H-NMR,13C-NMR, MS and elemental analyses.2. The influences about the kinds of substituents on the side chain were studied, the results showed that the ZnPc substituted with carboxyl has the best photosensitive activity, while low solubility and aggregation phenomena were observed in physiological environment.3. The 4,8 and 16 carboxyl modified ZnPc derivatives have been synthesized by the strategy of gradually increasing the side chain space steric hindrance of the ZnPcs. In order to reduce aggregation degree and enhance the photosensitivity of carboxyl modified ZnPc under physiological conditions, Studies of their properties showed that the increase of steric hindrance of ZnPcs can effectively inhibit aggregation and enchance the generation ability of reactive oxygen species (ROSs). Among them, ZnPc containing 16 carboxy mainly existed as monomers in aqueous solution. Besides, the ability to produce ROS was the best.4. The ZnPcs substituted with carboxylate have been synthesized and their solubility, aggregation and photochemical properties have been studied. Results showed they have good water solubility, and the increase of carboxylate groups on side chain can improve the aggregation and ROS generation ability of ZnPcs in aqueous solution.