title: Synchronous fluorimetric determination of salicylic acid and diflunisal in human serum using partial least-squares calibration.
abstract: The simultaneous determination of salicylic acid and diflunisal in human serum has been accomplished by synchronous fluorimetry, in combination with partial least-squares multivariate calibration. The total luminescence information of the analytes has been used to optimize the spectral data set for the calibration, by analysis of the three-dimensional excitation-emission matrices. The synchronous spectrum, maintaining a constant difference of Deltalambda = 128 nm between the emission and excitation wavelengths, has been selected as optimum to perform the determination. The method is based on the fluorescence of these compounds in chloroform containing 1% (v/v) acetic acid. Serum samples are treated with trichloroacetic acid to remove the proteins, and both analytes are extracted into chloroform-1% (v/v) acetic acid prior to the determination. For concentrations ranging from 60-240 mug ml(-1) of each drug, analytical recoveries range from 96% to 103% for salicylic acid and from 97% to 105% for diflunisal.
authors.forename: A
authors.initials: A
authors.lastname: Muñoz de la Peña
authors.forename: M D
authors.initials: MD
authors.lastname: Moreno
authors.forename: I
authors.initials: I
authors.lastname: Durán-Merás
authors.forename: F
authors.initials: F
authors.lastname: Salinas