Comparative Study for Determining Diuron and Chlorpyrifos at PPB Levels by First Derivative Spectra and Multivariate Calibration Methods

ABSTRACT The quantitative predictive abilities of derivative spectral analysis by using the zero-crossing point method were compared with the results obtained by the use of multivariate calibration methods. Mixtures of two pesticides, diuron and chlorpyrifos, were resolved by application of derivative spectrophotometry. Partial least squares (PLS-1 and PLS-2) and principal component regression (PCR), full spectrum calibration methods, were also applied, with previous optimization of the calibration matrix, using the absorption spectra and the first-derivative spectra. Both approaches were satisfactorily applied to the simultaneous determination of diuron and chlorpyrifos in synthetic mixtures. However, significant advantages were found in the determination of these pesticides in groundwater samples, previous solid-phase extraction with C18 cartridges, by application of different chemometric approaches when the calibration matrix was performed using the first derivative of the absorption spectra.

[1]  E. V. Thomas,et al.  Partial least-squares methods for spectral analyses. 1. Relation to other quantitative calibration methods and the extraction of qualitative information , 1988 .

[2]  Paul J. Worsfold,et al.  Partial least squares resolution of multianalyte flow injection data , 1993 .

[3]  J. Richard,et al.  Interferences in solid-phase extraction using C-18 bonded porous silica cartridges , 1988 .

[4]  A. Savitzky,et al.  Smoothing and Differentiation of Data by Simplified Least Squares Procedures. , 1964 .

[5]  S. Wold.  Cross-Validatory Estimation of the Number of Components in Factor and Principal Components Models , 1978 .

[6]  G. Font,et al.  Solid-phase extraction of organochlorine pesticides from water samples. , 1990 .

[7]  F. Salinas,et al.  Determination of oxytetracycline and doxycycline in pharmaceutical compounds, urine and honey by derivative spectrophotometry. , 1989, The Analyst.

[8]  A. G. Frenich,et al.  Simultaneous Determination of Atrazine and Chlorpyrifos in Pesticide Formulations, in Soils and Waters by Derivative Spectrophotometry and Ratio Spectra Derivative , 1994 .

[9]  A. G. Frenich,et al.  First derivative of the ratio spectra method for resolving iodide and thiocyanate in binary mixtures. , 1994, Talanta.

[10]  T. C. O'Haver,et al.  Numerical error analysis of derivative spectrometry for the quantitative analysis of mixtures , 1976 .

[11]  A. Espinosa-Mansilla,et al.  Multicomponent determination of flavour enhancers in food preparations by partial least squares and principal component regression modelling of spectrophotometric data. , 1993, The Analyst.

[12]  B. Kowalski,et al.  Partial least-squares regression: a tutorial , 1986 .

[13]  A. G. Frenich,et al.  Multicomponent determination of atrazine, diuron and chlorpyrifos in groundwaters and soils by spectrophotometry using multivariate calibration , 1994 .

[14]  Thomas C. O'Haver,et al.  Derivative and Wavelength Modulation Spectrometry , 1979 .

[15]  E. V. Thomas,et al.  COMPARISON OF MULTIVARIATE CALIBRATION METHODS FOR QUANTITATIVE SPECTRAL ANALYSIS , 1990 .

[16]  Simultaneous determination of 2-furfuraldehyde, 5-hydroxymethylfurfuraldehyde and malonaldehyde in mixtures by derivative spectrophotometry and partial least-squares analysis , 1993 .