Improved calculation of the net analyte signal in inverse multivariate calibration

Abstract

SUMMARYThe net analyte signal (NAS) is the part of the measured signal that a calibration model relates to the property of interest (e.g. analyte concentration). Accurate values of the NAS are required in multivariate calibration to calculate analytical figures of merit such as sensitivity, selectivity, signal-to-noise ratio and limit of detection. This paper presents an improved version of the calculation method for the NAS in inverse models proposed by Lorber et al. (Anal. Chem. 1997; 69: 1620). Model coefficients and predictions calculated with the improved NAS are the same as those from the common equations of principal component regression (PCR) and partial least squares (PLS) regression. The necessary alterations to the calculations of sensitivity, selectivity and the pseudounivariate presentation of the model are also provided.

Uncertainty estimation and figures of merit for multivariate calibration (IUPAC Technical Report)

“…(For refinements of the original calculation method, see refs. [136][137][138].) In other words, the calibration curve is obtained by replacing the measured instrumental signal used in univariate calibration (e.g., absorbance at a single wavelength) by the NAS (r * ).…”

Simultaneous Determination of Phenol and Mononitrophenol Isomers Using PLS Regression and Conventional and Derivative Spectrophotometry

“…44,[45][46][47][48] In this investigation, the LOD and LOQ have been calculated from the univariate definitions as described by Garcia et al 49 and Ketterer et al 50 For each individual component, four standard mixtures were prepared so that the concentration of the analyte was kept constant at a low level close to the LOQ, and that of other components was varied. The concentration of the analyte in the mixtures was estimated by the TABLE 4 -The calculated LOD and LOQ (in µg ml -1 ).…”

Determination of figures of merit for near-infrared and raman spectrometry by net analyte signal analysis for a 4-component solid dosage system

“…Certain NAS techniques allow the determination of predicted concentrations using the following equation 10,18 : …”

“…Multiple algorithms for calculating NAS have been reported in the literature, 17,18 with the method of computation and resulting output differing. In this work, the method proposed by Bro and Andersen is used.…”

“…[10][11][12][13][16][17][18][19][21][22][23] was generated. The approximate median particle size of the theophylline, lactose, MCC, and starch (reported by documentation from their respective suppliers) was~90,~100,~180, and~17 μm, respectively.…”