The synchronous fluorescence spectrometry was used for the first time to eliminate the interference between the emission of the small-molecule drugs and the determination of the endogenous fluorescence of the protein.The synchronous fluorescence spectrometry and UV-Vis were applied to study the interaction between Tetramethrin and BSA in physiological buffer(pH 7.4).The results of the experiment proved that the quenching mechanism of fluorescence of BSA by Tetramethrin was a static quenching procedure.The number of binding potential point(n) and the association constant(K0) at 298K were n=1.13 and K0=1.428×105L·mol-1,respectively.The enthalpy change and the entropy change were calculated to be △H=29.69KJ·mol-1,△S=211.65J·K·mol-1,which showed that the binding mode was mainly the reflection of the hydrophobic interaction.On the basis of the Frster’s non-radiative energy transfer mechanism,the binding distance(r) and the rate of energy transfer(E)between donor(BSA) and acceptor(Tetramethrin) were obtained to be r=5.15nm,E=0.117,respectively.
