Achieving bilinearity in non-bilinear augmented first order kinetic data applying calibration transfer

Abstract

In this paper a calibration transfer method is used to achieve bilinearity for augmented first order kinetic data. First, the proposed method is investigated using simulated data and next the concept is applied to experimental data. The experimental data consists of spectroscopic monitoring of the first order degradation reaction of carbaryl. This component is used for control of pests in fruits, vegetables, forages, cotton and other crops. It is highly toxic and likely human carcinogen, and is lethal to many non-target beneficial insects. The kinetic experiment is performed at different pH-values and emission wavelengths using an excitation wavelength equal to 275nm. Rate constants of different data matrices at different pH values were calculated based on a hard modeling method. Analysis of simulated and experimental data shows that if there is a deviation from bilinearity, applying the model based methods to augmented datasets leads to inaccurate results. The application of a calibration transfer method as an additional step in the hard modeling procedure improves the results, and accurate estimation of reaction rate constants are obtained. The proposed method was compared to Local Spectra Mode of Analysis (LSMA) which was proposed by Puxty et al. A comparison of the results shows that the proposed method is more efficient than LSMA and leads to less uncertainty in estimated rate constants and less percent error in the relative residuals.