In-situ photochemical spectrofluorimetric detection of 9,10-anthraquinone-labeled bovine serum albumin

Interaction of emodin, aloe-emodin, and rhein with human serum albumin: a fluorescence spectroscopic study

The interaction of the dihydroxyanthraquinones, emodin (1), aloe-emodin (2), and rhein (3) with human serum albumin (HSA) has been studied through fluorescence spectroscopy. Quenching studies and the association constant of the anthraquinoid compounds 1, 2, and 3 in the presence of HSA were estimated. The binding and quenching studies suggest that only emodin (1) may serve as a useful fluorescence probe for structure/function studies of different emodin binding proteins. No photoinduced binding was observed after irradiation of compounds 1, 2, and 3 in presence of human serum albumin.

Improvement of the acridine orange–protein–surfactant system for protein estimation based on aromatic ring stacking effect of sodium dodecyl benzene sulphonate

The fluorescence of acridine orange (AO) is greatly quenched by the anionic surfactant sodium dodecyl benzene sulphonate (SDBS), but when protein is added into the AO-SDBS system, the fluorescence intensity of the latter is enhanced again. Based on this, a new fluorimetric method of determination of protein was developed. Under optimum conditions, the enhanced intensity of fluorescence is in proportion to the concentration of protein, such as bovine serum albumin (BSA), human serum albumin (HSA) and egg albumin (EA), over a wide range with detection limits at the 10(-9) g/mL level. This method has been satisfactorily used for the determination of protein in samples. We compared results using 280 nm and 490 nm excitation wavelengths and the mechanism of the assay.