Study on the Interaction of [Ni( Phen)( 5-Fu)_2]( NO_3)_2 and Bovine Serum Albumin by Fluorescence

Objective To investigate the interaction mechanism of [Ni( Phen)( 5-Fu)2]( NO3)2with bovine serum albumin( BSA). Methods A complex of [Ni( Phen)( 5-Fu)2]( NO3)2was designed and synthesized using Ni( NO3)2,fluorouracil( 5-Fu),1,10-phenanthrotine( Phen) as starting materials,and it was characterized by elemental analyses and IR spectra. The interaction of [Ni( Phen)( 5-Fu)2]( NO3)2with bovine serum albumin was studied using fluorescence spectroscopy in the pH 7. 00 Tris-HCl buffer system. Results The research of fluorescence spectroscopy showed that these interactions resulted in the endogenous fluorescence quenching of bovine serum albumin,which belonged to a static quenching mechanism,and the complex could effect the conformation of bovine serum albumin. The quenching rate constant is 4. 04 × 1 012 L·mol-1·s-1,the binding constants Ka is 8. 14 × 105 L·mol-1and the binding sites of the static quenching n is 1. 32. Moreover,the complex could quench 91. 0% of tryptophane( Trp) group in the bovine serum albumin surface. Conclusions [Ni( Phen)( 5-Fu)2]( NO3)2would be an excellent quenching reagent in the future.