Deconvolution oft be fluorescence spectra into its component Gaussians: A method to analyze the binding of coumarin to bovine serum albumin

7-N,N-Diethylamino-4-methylcoumarin, (cou-1), a readily available laser dye binding to bovine serum albumid (BSA), at room temperature has been studie d by steady state fluorescence spectroscopy. Existing methods of analysis o f the binding to obtain the binding parameters are based on the change in f luorescence intensity at a particular wavelength. These methods are not con venient when there is a gradual shift in the emission maxima for increasing protein concentration. In this paper we present a method to obtain the bin ding constants of cou-1 to BSA using a Windows '95 based package to deconvo lute the asymmetrical spectrum (fluorescence intensity versus wave number c urve) into two Gaussians, each corresponding to the binding of the fluoroph ore to a particular site. This method is convenient to analyze the binding constant data and obtain the binding parameters of each binding site, and c an also provide information about the microenvironment of each site, relati ng micropolarity and microviscosity.