Abstract: The interaction between (E)-2((1,4-dihydroxy-9,10-anthraquinone-2-yl) methylene)-N-(4-methoxyphenyl) hydrazinecarbothioamide(EN) and human serum albumin(HSA) is investigated by fluorescence in Tris-HCl buffer solution(pH=7.4). The results of fluorescence experiments and three-dimensional fluorescence spectra indicate that the presence of EN can change the polarity of the hydrophobic microenvironment and induce minor changes of the secondary structure of HSA. Under the optimum conditions, the linear range of the protein is 1.380~165.6 mg/L and the detection limit is 0.414 mg/L with the synchronous fluorescence method. The contents of the proteins in human serum, saliva and urine samples are detected and the recovery is ranged from 98.4% to 105%. The effects of coexistent material are also investigated. The results of synchronous fluorescence method are in good agreement with the Coomassie Brilliant Blue(CBB) method.

Key words: (E)-((dihydroxyanthraquinoneyl)methylene)-N-(methoxyphenyl)hydrazinecarbothioamide, human serum albumin, three-dimensional fluorescence spectra, synchronous fluorescence Spectrum