INVESTIGADORES
CULZONI Maria Julia
congresos y reuniones científicas
Título:
Effect of PDS, baseline correction and mean centering as signal pretreatments in the resolution of eight tetracyclines by application of MCR-ALS to HPLC-DAD data from effluent wastewater samples.
Autor/es:
M.D. GIL GARCÍA, M.M. DE ZAN, M.J. CULZONI, R. SANTIAGO VALVERDE, G.G. SIANO, H.G. GOICOECHEA, M. MARTÍNEZ GALERA.
Lugar:
Pollensa, España
Reunión:
Simposio; IX Internacional Symposium on Analytical Methodology in The Environmental Field.; 2007
Resumen:
The effect of Piecewise Direct
Standardization (PDS), Baseline Correction and Mean Centering approaches was
evaluated in the performance of Multivariate Curve Resolution (MCR-ALS) for the
resolution of three-way data sets from liquid chromatography with diode-array
detection (LC-DAD).
Eight tetracyclines (tetracycline,
oxytetracycline, chlorotetracycline, demeclocycline, methacycline, doxycycline,
meclocycline and minocycline) were firstly isolated from 250 mL effluent
wastewater samples by Solid Phase Extraction (SPE) with Oasis MAX 500 mg / 6 mL
cartridges and then separated on an
Aquasil C18 150 mm
× 4.6 mm
(5 μm particle size) column and detected by LC-DAD. Previous experiments,
carried out with Milli-Q water samples, showed considerable losses of the most
polar analytes (minocycline, oxitetracycline and tetracycline) due to
breaktrough. PDS was applied to overcome this important drawback. Conversion of
standard chromatograms obtained from standards prepared in solvent was
performed obtaining a high correlation with those corresponding to real
situation (r2 = 0.98).
The sample matrix caused
a large baseline drift, and also additive interferences were present at the
retention times of the analytes. These problems were solved with the baseline
correction method proposed by Eilers and Mean Centering.
The number of interferences obtained
by MCR-ALS from uncorrected data sets was higher, as expected, and the quality
of the spectral and chromatographic profiles was dramatically worse.