Determination of Peak Purity in HPLC by Coupling Coulometric Array Detection and Two-Dimensional Correlation Analysis

Area of Science:

• Analytical Chemistry
• Chromatography
• Spectroscopy

Background:

• Chromatographic peak purity is crucial for accurate compound identification and quantification.
• Overlapping peaks can lead to misinterpretation of results in complex sample analyses.

Purpose of the Study:

• To evaluate the utility of two-dimensional correlation (2D-corr) analysis for assessing chromatographic peak purity.
• To demonstrate the capability of 2D-corr analysis in detecting coeluting species within chromatographic peaks.

Main Methods:

• Two-dimensional correlation (2D-corr) analysis was applied to chromatographic data.
• High-performance liquid chromatography (HPLC) coupled with a 16-detector coulometric array was used.
• Mass spectrometry (MS) was employed for coeluting species identification.

Main Results:

• 2D-corr analysis successfully identified the number of peaks and revealed overlapping species.
• Analysis of Capsicum chili extracts showed at least three overlapping species on a single peak.
• Coeluting species were identified as quinic acid, ascorbic acid, and phenylalanine.

Conclusions:

• 2D-corr analysis is a valuable tool for verifying chromatographic signal purity.
• The method effectively detects and helps resolve overlapping compounds in complex mixtures.
• This approach enhances the reliability of chromatographic analyses.