Resolution of binary mixtures of theophylline (THEO), montelukast (MKST) and loratadine (LORA) with minimum sample pretreatment and without analyte separation has been successfully achieved by multivariate spectrophotometric calibration, together with partial least-squares (PLS-1), principal component regression (PCR) and hybrid linear analysis (HLA). Data of analysis were obtained from UV–Vis ...

Multivariate calibration methods (partial least squares calibration, back propagation multilayer perceptrons networks, radial basis functions and generalized regression neural networks) were applied to the simultaneous fluorometric quantification of levofloxacin, garenoxacin and grepafloxacin, without previous separation steps. A data matrix was obtained by registering the emission spectra of m...

Simultaneous spectrophotometric determination of salicylamide and paracetamol by H-point standard addition method (HPSAM) and partial least squares (PLS) calibration is described. The results showed that simultaneous determinations could be performed with the ratio 0.2:5–20:1 for salicylamide – paracetamol. A partial least – squares multivariate calibration method for the analysis of binary mix...

The analysis of kinetic data monitored using spectroscopic techniques and its resolution into its unknown components is described. Independent Component Analysis (ICA) can be considered a calibration free technique with the outcome of the analyses being the spectral profiles of the unknown species. This enables the realisation of qualitative information concerning the identification of the numb...

The robustness of a dual-beam, optical null, Fourier-transform near-infrared (FTNIR) spectrometer was investigated by means of online, near-infrared measurements and predictions of urea concentrations in spent dialysate during hemodialysis treatment. Simple multivariate calibration using a few factors based on a small number of prepared samples provided stable and accurate predictions over a pe...

Second-order calibration and multivariate spectroscopic-kinetic measurements in the visible region are proposed to improve the Jaffé method for creatinine assay. Analyses performed on synthetic mixtures containing bilirubin, glucose, and albumin confirm that second-order calibration is useful for creatinine determination in human serum. Quantitative determinations of creatinine with the paralle...

Corresponding Author: Lauro Cassio Martins de Paula Institute of Informatics, Federal University of Goiás, Brazil Email: [email protected] Abstract: The development of efficient algorithms for variable selection becomes important to deal with large and complex datasets. Most works in quantitative chemical analysis have used Genetic Algorithms (GAs) as a reference method to select variabl...

Corresponding Author: Anderson Silva Soares Federal University of Goias, Goiania, Brazil Email: [email protected] Abstract: One of the main problems of quantitative analytical chemistry is to estimate the concentration of one or more species from the values of certain physicochemical properties of the system of interest. For this it is necessary to construct a calibration model, i.e., to dete...

The objective of this paper is to present a review of different calibration and classification methods for functional data in the context of chemometric applications. In chemometric, it is usual to measure certain parameters in terms of a set of spectrometric curves that are observed in a finite set of points (functional data). Although the predictor variable is clearly functional, this problem...

Background: Two simple, precise and accurate multivariate calibration methods, partial least square (PLS) and principal component regression (PCR) have been applied for the simultaneous determination and dissolution profile evaluation of atorvastatin (ATV) and ezetimibe (EZT) in their binary mixtures and commercial tablets. Due to the closely overlapping spectral bands of the mentioned drugs, s...