On the Interaction of Protein and Coordination Complex of 5′-Nitro-salicyfluorone with Mo(Ⅵ)

5′-Nitro-salicyfluorone (5′-NSF) was synthesized,and its coordination complex with Mo(Ⅵ) with binding ratio n5′-NSF∶nMo(Ⅵ) of 1 to 1 was prepared which was used as a new photometric probe.Mechanism of the interaction of this complex with protein was studied by UV-VIS spectrophotometry.It was found that the absorption maximum of coordination complex of 5′-NSF-Mo(Ⅵ) lies at the wavelength of 532 nm in an acetate buffer medium of pH 3.6,and that the absorption intensity was enhanced by the presence of appropriate amount of OP.However,due to the interaction of this coordination complex with protein,the absorption intensity was deceased,and the magnitude of decrease in absorbance (ΔA) was found to keep linear relationship with mass concentration of protein in the ranges of 1.0 to 35.0 and 1.0 to 40.0 mg·L-1 for BSA and HSA and with values of molar absorptivity 1.02×106 and 1.03×106L·mol-1·cm-1 respectively.The proposed method was used in the determination of protein in samples of urine,milk powder and human serum,giving values of recovery in the range of 92.8%-96.0% and RSD′s (n=5) less than 2.0% respectively.