Chapter 10 - Chemometric Resolution of Complex Higher Order Chromatographic Data with Spectral Detection

Abstract One- and two-dimensional chromatography has been coupled with spectral detection in a variety of ways. Some of the most popular instrumental platforms will be covered in this chapter: liquid chromatography coupled with multiwavelength diode array detection (LC–DAD), gas chromatography with mass spectrometry (GC–MS), comprehensive two-dimensional liquid chromatography with DAD (LC × LC–DAD), and comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC × GC–TOFMS). Since these instruments are commonly applied to study complex samples, the resulting data are also very complex, and analyte peaks commonly overlap. Chemometric methods are often used to mathematically resolve (or unmix) the overlapped analyte peaks, which leads to successful analyte identification and quantification. The design and implementation of a particular instrumental platform can significantly impact various underlying aspects of the data structure, whether second order or third order, causing benefits and challenges for chemometric methods. The benefits and challenges that appear at the interface between hyphenated chromatography and chemometrics will be explored for several mathematical resolution methods, including multivariate curve resolution-alternating least squares (MCR-ALS), generalized rank annihilation method (GRAM), and parallel factor analysis methods (PARAFAC and PARAFAC2).