Studies on the Interaction between NaVO_3 and Bovine Serum Albumin by Fluorescence Method

The interaction between NaVO3 and bovine serum albumin (BSA) was investigated by absorption spectrometry and fluorescence measurement. The binding constants were also obtained and the effect of UV C(253.7 nm) exposure on the values of binding constants was discussed. It is proved that the fluorescence quenching of BSA by NaVO3 is a result of the formation of NaVO3 complex in the solution. The mechanism of quenching belongs to static quenching and the association constants between NaVO3 and BSA are Ks=0.357×104(25 ℃), Ks=0.667 × 104 (30 ℃), Ks=1.437 × 104 (35 ℃). Based on the mechanism of energy transfer of dipole-dipole interaction between the donor and acceptor,we have determined the distance between 214-tryptophane residue of BSA and NaVO3 molecule to be R=1.069 5 nm (25 ℃), R=1.078 2 nm (30 ℃), R=1.080 6 nm (35 ℃).