Standardization of Fiber-Optic Probes for Near-Infrared Multivariate Calibrations

The standardization of Fourier transform near-infrared (FT-NIR) spectrometers equipped with fiber-optic probes was investigated. FT-NIR spectra of caustic brines for an industrial process were measured on two different instruments. Calibration transfer across the instruments and probes was studied by employing calibration models built on one instrument to predict properties from spectra measured on the other. The transfer was examined by using spectra without and with preprocessing. The preprocessing methods included a Savitzky–Golay (SG) derivative polynomial filter, a procedure based on a finite impulse response (FIR) filter, and a combination of both. In addition to being a preprocessing technique, the FIR filter is also a standardization method that transforms the instrument response function of one instrument to match that of another. The transformation is performed over a moving processing window without the use of transfer standards. In this study, application of the FIR filter to first-derivative spectra provided the best multivariate calibration models and led to the successful transfer of calibration across different probes and spectrometers.

[1]  Bruce R. Kowalski,et al.  Temperature-compensating calibration transfer for near-infrared filter instruments , 1993 .

[2]  B. Kowalski,et al.  Improvement of multivariate calibration through instrument standardization , 1992 .

[3]  Chris W. Brown,et al.  Calibration Transfer from Sample Cell to Fiber-Optic Probe , 1997 .

[4]  J. Shenk,et al.  Calibration Transfer Between near Infrared Reflectance Spectrophotometers , 1985 .

[5]  F. McLennan,et al.  Process analytical chemistry in perspective , 1995 .

[6]  Jeffrey J. Kelly,et al.  Measurement of caustic and caustic brine solutions by spectroscopic detection of the hydroxide ion in the near-infrared region, 700-1150 nm , 1989 .

[7]  Marcelo Blanco,et al.  Wavelength Calibration Transfer between Diode Array UV-Visible Spectrophotometers , 1995 .

[8]  Onno E. de Noord,et al.  The influence of data preprocessing on the robustness and parsimony of multivariate calibration models , 1994 .

[9]  Onno E. de Noord,et al.  Multivariate calibration standardization , 1994 .

[10]  J. Shenk,et al.  New Standardization and Calibration Procedures for Nirs Analytical Systems , 1991 .

[11]  Bruce R. Kowalski,et al.  Calibration Transfer and Measurement Stability of Near-Infrared Spectrometers , 1992 .

[12]  B. Kowalski,et al.  Multivariate instrument standardization , 1991 .

[13]  M. Forina,et al.  Transfer of calibration function in near-infrared spectroscopy , 1995 .

[14]  Desire L. Massart,et al.  Improvement of the piecewise direct standardisation procedure for the transfer of NIR spectra for multivariate calibration , 1996 .

[15]  Bruce R. Kowalski,et al.  Piece-Wise Multiplicative Scatter Correction Applied to Near-Infrared Diffuse Transmittance Data from Meat Products , 1993 .

[16]  T. B. Blank,et al.  Transfer of Near-Infrared Multivariate Calibrations without Standards. , 1996, Analytical chemistry.

[17]  D. Massart,et al.  Elimination of uninformative variables for multivariate calibration. , 1996, Analytical chemistry.

[18]  P. Gemperline,et al.  Appearance of discontinuities in spectra transformed by the piecewise direct instrument standardization procedure. , 1996, Analytical chemistry.

[19]  S. R. Crouch,et al.  Frequency response of initial point least squares polynomial filters , 1987 .

[20]  Desire L. Massart,et al.  Calibration transfer across near-infrared spectrometric instruments using Shenk's algorithm: effects of different standardisation samples , 1994 .

[21]  D. Massart,et al.  Standardization of near-infrared spectrometric instruments , 1996 .

[22]  D. Massart,et al.  Standardisation of near-infrared spectrometric instruments: A review , 1996 .

[23]  Desire L. Massart,et al.  Modified Algorithm for Standardization of Near-Infrared Spectrometric Instruments , 1995 .

[24]  Desire L. Massart,et al.  Standardization of near-infrared spectra in the wavelet domain , 1997 .

[25]  Bruce R. Kowalski,et al.  Additive Background Correction in Multivariate Instrument Standardization , 1995 .