Simultaneous determination of flufenamic and meclofenamic acids in human urine samples by second-order multivariate PARAFAC calibration of micellar-enhanced excitation-emission fluorescence data

ALEJANDRO CESAR OLIVIERI; MUÑOZ DE LA PEÑA, A.; MORA DIEZ, N.; BOHOYO GIL, D.; M. ESCANDAR, G.

Lugo

Congreso; XI Simposio Internacional de Espectroscopía de Luminiscencia; 2006

Sociedad Internacional de Espectroscopia de Luminiscencia

Flufenamic and meclofenamic acids are potent analgesic and anti-inflammatory drugs. They have been used in the treatment of arthritis and other illnesses related to muscular-skeletal problems. A new method for the determination of flufenamic and meclofenamic acids in urine samples is proposed, by recording the excitation-emission fluorescence matrices (EEMs) in the presence of hydroxypropiltrimethylammoniumbromide (HTAB). The method is combined with the second order multivariate calibration method parallel factor analysis PARAFAC. The changes in the UV-visible and fluorescence spectra of solutions of each compound in the presence and absence of HTAB, as a function of pH, were analyzed. The obtained data were used for the estimation of the deprotonation constant values, employing an appropriate MATLAB routine. In the case of PARAFAC, in order to determine the optimal number of factors for each test human urine sample, the value of the core consistency parameter was analyzed as a function of a trial number of components. Once the number of components was estimated, the array formed by joining the EEMs for the test sample and those obtained by standard addition was subjected to decomposition. The identification of the chemical constituents under investigation, is required before quantitation, by resorting to the pseudo-univariate calibration graph provided by PARAFAC.