Four-component determinations using phase-resolved fluorescence spectroscopy

Abstract

Abstract : A method for the determination of the Individual components in a quaternary system of anthracene derivatives is presented. The method employs phase-resolved fluorescence spectroscopy (PRFS) in conjunction with wavelength selection for the simultaneous determination of anthracene, 1-chloroanthracene, 2-chloroanthracene, and 9-chloroanthracene in mixtures containing these four species. The design and use of a least-squares routine for the calculation of the amplitude and phase phi of the cosine curve that describes the phase- resolved fluorescence intensity (PRFI) as a function of detector phase angle (phi sub D) for each of the individual components are discussed. The fitting of PRFI vs. phi sub D for mixtures is carried out by using a fifth-order polynomial routine. The results of the least-squares and fifth-order polynomial analyses are combined to generate a series of simultaneous equations which are solved for the analytical concentrations of the four components in each mixture by using a Gaussian-Newton iterative procedure written in Apple BASIC.