Multivariate curve resolution-correlation optimized warping applied to the complex GC–MS signals; toward comparative study of peel chemical variability of Citrus aurantium L. varieties

Publication date: Available online 30 July 2018Source: Microchemical JournalAuthor(s): Fatemeh Azimi, Mohammad Hossein FatemiAbstractMultivariate curve resolution based correlation optimized warping (MCR-COW) was proposed as an efficient alignment method to correct the undesirable elution time shifts where co-eluting and shift occurred at the same time and the use of COW algorithm on the raw data often fails. For this purpose, the primary implementation of extended multivariate curve resolution- alternating least squares (MCR-ALS) helped to reduce the underlying complexity of gas chromatography–mass spectrometry (GC–MS) data representing the pure elution and spectral signatures. Afterward, the resolved elution profiles aligned component by component using COW algorithm. Reconstituting of the corrected column wise augmented data was conducted by multiplying of aligned augmented elution profiles with their corresponding spectral profiles to reanalysis by MCR-ALS under optional application of trilinearity constraint. The results obtained from the proposed strategy (MCR-COW-MCR) compared to two common methods MCR-ALS and COW-MCR under application of the same constraints in statistical terms such as lack of fit (LOF), percent of variance explained (R2) under the optimum conditions, concentration and spectral correlation coefficient (R). Also, MCR-BAND method was served to evaluate the extent of rotational ambiguity associated to MCR-ALS and MCR-COW-MCR recovered solutions. Her...
Source: Microchemical Journal - Category: Chemistry Source Type: research