Study on the mechanism of interaction between meso-tetracarboxyphenyl porphyrin and bovine serum albumin by fluorescent method

The mechanism of interaction between bovine serum albumin(BSA)and meso-tetracarboxyphenyl porphyrin(TCP)was studied by fluorescent method.The binding constants of the reaction at 25℃,36℃ and 42℃ were calculated by Stern-Volmer equation and Lineweaver-Burk double-reciprocal function.The KSV were 1.17×105,1.06×105,1.01×105 L·mol-1 and KLB were 5.00×104,2.22×104,1.11×104 L·mol-1,respectively.Therefore,the sort of quenching between TCP and BSA was determined as static qu enching.By the theory of Frster non-radiation energy transfer,the transfer efficiency was calculated to be 0.444 and the binding distance was 2.78nm,which was less than 7nm,so,the interaction was similar to the non-radiation energy transfer.According to the thermodynamic parameters,the main sorts of binding force between TCP and BSA could be judged as hydrogen bond and van der Waals force whenΔG0,ΔH0 and ΔS0.All of these provided some references for further pharmacokinetic study of meso-tetracarboxyphenyl porphyrin and its ramifications.