Multivariate calibration procedures applied to high performance liquid chromatography coupled to fast-scanning fluorescence detection for the determination of fluoroquinolones in different matrices

ESPINOSA MANSILLA, A.; MUÑOZ DE LA PEÑA, A.; ARANCIBIA, J. A.; CAÑADA-CAÑADA,F.; ESCANDAR, G. M.; IBAÑEZ, G. A.; OLIVIERI, A. C.

San Sebastián, España.

Congreso; XV Reunión de la Sociedad Española de Química Analítica; 2009

Sociedad Española de Química Analítica

Different second-order multivariate calibration algorithms, namely parallel factor analysis (PARAFAC), N-dimensional partial least-squares (N-PLS) and multivariate curve resolution-alternating least-squares (MCR-ALS) have been compared for the analysis of eight fluoroquinolones in aqueous solutions, including some human urine samples. The assayed analytes were: pipemidic acid (PIPE), belonging to the first generation of quinolone antibiotics; marbofloxacin (MARBO), ofloxacin (OFLO), norfloxacin (NOR), ciprofloxacin (CIPRO), enrofloxacin (ENRO) and lomefloxacin (LOME) belonging to the second generation; and danofloxacin (DANO) belonging to the third generation. These analytes were chosen due to their importance in human medicine (second-generation fluoroquinolones) and also in veterinary medicine (MARBO, ENRO, and DANO). Data were measured in a short time with a chromatographic system operating in the isocratic mode. The detection system consisted of a fast-scanning spectrofluorimeter, which allows one to obtain second-order data matrices containing the fluorescence intensity as a function of retention time and emission wavelength. The developed approach enabled us to determine eight analytes with overlapped profiles, without the necessity of applying an elution gradient, and thus significantly reducing both the experimental time and complexity. The study was employed for the discussion of the scopes of the applied second-order chemometric tools. The quality of the proposed technique coupled to each of the evaluated algorithms was assessed on the basis of the figures of merit for the determination of fluoroquinolones in the analyzed water and urine samples. Univariate calibration of four analytes led to limits of detection in the range 20-40 ng/mL and root mean square errors for the validation samples in the range 30-60 ng/rnL (corresponding to relative prediction errors of 3-8%). The ranges for second-order multivariate calibration (using PARAFAC and N-PLS) of the remaining four analytes were: limit of detection, 2-8 ng/mL , root mean square errors, 3-50 ng/mL and relative prediction errors, 1-5%.