EXCEL TUTORIAL FOR PARAMETRIZATION OF ANALYTICAL CURVES
Keywords:
analytical curve, parameters of the calibration curve, statistical modelsAbstract
Analytical chemistry uses empirical procedures to determine analytes concentration through instrumental techniques that relate the analytical signal, instrumental response (y) to the analyte concentration (x). The signal measured by the instrument is generally a function of the analyte concentration, which is plotted (y = fx), commonly referred to as analytical curve or standard curve. Linear functions are commonly used for this purpose, thus the linearization of this function is necessary to calculate the concentration of the analyte and, to properly express the result, statistical processing of the experimental data is required. Usually, students of instrumental analytical chemistry courses find it difficult to process and interpret results when using a calibration curve and understand its parameters. In that sense, it is proposed a linear regression tutorial of experimental data for the calculation of all the parameters that characterize an analytical curve, through a procedure using Excel spreadsheet MS Office 2016. A routine of calculations was created using experimental data from the spectrophotometric determination of protein, using the standard BSA and pH meter calibration, but it can be extended to other procedures where the calculation is necessary.
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References
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