Investigation of interaction of fluorescent marker Bengal Rose with human serum albumin at various values of pH

The interaction of fluorescent marker Bengal Rose with human serum albumin (HSA) at various values of pH has been studied by steady-state fluorescence, absorption spectroscopy, and Raman spectroscopy. The decrease of degree of molecular association of Bengal Rose in solutions at HSA addition is revealed. It is shown that degree of molecular association of Bengal Rose monotonously decreases with increase of values of pH. It is registered that in solutions with HSA there are quenching of fluorescence and red shift of maximum of fluorescence spectrum of Bengal Rose. Various theoretical models are used to determine the constants of quenching of fluorescence of Bengal Rose by HSA, corresponding to binding of Bengal Rose to HSA molecules, at various values of pH. It is shown that binding of Bengal Rose with HSA takes place through Binding Center I of HSA. The received results of researches of interaction of Bengal Rose with HSA show the perspectives of this marker in structural researches of HSA and in modeling of binding of some medical drugs to HSA.