ABSTRACT
Many methods for the identification and determination of analytes in complex matrices are based on chromatographic techniques coupled with diverse detection systems. Exploratory approaches help to define the complexity of chromatographic data in terms of number and overlap of eluting compounds, to clarify elution patterns, and to detect impurities and minor compounds with methodologies much more performing than classical visual inspection. The underlying model of the chromatographic measurement is identical to the model used in factor analysis methods, the goal of which is decomposing a data table into a bilinear model of factors, representing the different sources of variance of the data. These methods have been widely applied for the determination of the number of compounds, peak purity problems, resolution of overlapped compounds, or extension to simultaneous analysis of multiple runs to obtain qualitative and quantitative information. Local rank analysis methods take advantage of the structured elution pattern of chromatographic processes, that is, of the sequential elution of compounds.
