Abstract:

The interactions between 1-Keto-2-(p-dimethylaminobenzal)-tetrohydronaphthalene（KDTN） and human serum albumin(HSA) have been studied by fluorescence and UV-Vis absorption spectra. The binding of KDTN to HSA quenches the tryptophan residue fluorescence and the results show that static quenching occurrs together with the complex formation. The binding constant and binding sites of KDTN to HSA at pH=7.43 are measured at different temperatures according to the double logarithm regression curve. In addition, the thermodynamic data show that KDTN molecules enter the hydrophobic cavity of HSA via Van der Waals force or hydrogen bond. Finally, the synchronous fluorescence spectra show that the microenvironment of the tryptophan residues does not show significant effect on the conformation.

Key words: Keto-(p-Dimethylaminobenzal)-Tetrohydronaphthalene, human serum albumin, Fluorescence spectrometry