3.1. Implementation of HPLC-DAD/MCR-ALS to resolve DC and NAL in
mixture
As can be seen in HPLC-DAD chromatogram (Fig. 1A) and the
two dimensional contour plots (Fig. 1B) of the standard solution,
DC and NAL are two compounds that have partly overlapped
chromatograms. In this study, the MCR-ALS algorithm was applied
on retention time ranging between 30 and 35 min, in which the
overlapped chromatograms of these two compounds are seen. The
exact peak area of these two compounds was calculated with the
help of MCR-ALS using MCRC software [24]. The steps that were
applied for obtaining the peak integration of NAL and DC by this
software are as follows: (1) baseline correction and denoising of
the chromatograms (Fig. 1C); (2) chemical rank determination by
principle component analysis (PCA) for the determination of the
number of chemical components in that retention time range;
(3) local rank analysis by fixed-size moving window evolving
factor analysis (FSMW–EFA) for representing the overlapping