Comprehensive chemical fingerprinting by LC×LC-fluorescence and data-driven chemometric modelling for unsupervised...

Area of Science:

• Analytical Chemistry
• Food Science
• Chemometrics

Background:

• Comprehensive two-dimensional liquid chromatography (LC × LC) offers high-resolution separation for complex samples.
• Food profiling traditionally relies on targeted analyses, which may miss crucial chemical information.
• Chemometric approaches are essential for extracting meaningful patterns from complex chromatographic data.

Purpose of the Study:

• To develop and apply an optimized LC × LC method with absorbance and fluorescence detection for food profiling.
• To evaluate the capability of LC × LC profiles as chemical fingerprints for sample characterization.
• To integrate chemometric strategies for data-driven analysis and enhanced chemical differentiation.

Main Methods:

• Development and optimization of a comprehensive two-dimensional liquid chromatography (LC × LC) protocol.
• Utilisation of both absorbance (UV) and fluorescence detection modes.
• Application of chemometric techniques, including PARAFAC, Principal Component Analysis (PCA), and Hierarchical Cluster Analysis (HCA).
• Exploration of mid-level data fusion by integrating UV and fluorescence data.

Main Results:

• The optimized LC × LC method demonstrated enhanced resolution and analytical performance for food profiling.
• Fluorescence detection provided deeper chemical insights compared to UV detection alone.
• Unsupervised analyses using PARAFAC scores revealed distinct clustering patterns related to geographical origin, composition, and producer.
• Data fusion of UV and fluorescence signals further improved the ability to distinguish between samples.

Conclusions:

• LC × LC coupled with chemometrics offers a powerful, non-targeted approach for food profiling.
• The developed method provides meaningful chemical differentiation, serving as a reliable alternative to conventional techniques.
• Combining complementary detection modes (UV and fluorescence) significantly enhances analytical capabilities for complex food matrices.