Quantification of Macular Carotenoids over a Wide Dynamic Range in Plant Matrices and Caco-2 Cells Using a Single...

Area of Science:

• Analytical Chemistry
• Nutritional Science
• Biochemistry

Background:

• Lutein and zeaxanthin are crucial macular carotenoids with protective roles against eye diseases.
• Their low bio-accessibility and structural similarity pose significant challenges for accurate quantification in various biological and food matrices.
• Existing quantification methods lack a unified approach for diverse matrices and concentration ranges, hindering comprehensive analysis.

Purpose of the Study:

• To develop and validate a single, unified liquid chromatographic method for the separation and quantification of lutein and zeaxanthin.
• To establish an effective extraction method, including alkaline hydrolysis, for improved recovery of these carotenoids.
• To demonstrate the method's applicability across diverse matrices, including food, digesta, and Caco-2 cells, and over a broad dynamic range.

Main Methods:

• An alkaline hydrolysis extraction procedure was employed to enhance carotenoid release.
• A single reverse-phase liquid chromatography method utilizing a C30 column and common mobile phase solvents was developed.
• The method was validated for accuracy, precision (RSDs), and applicability to both Photodiode Array (PDA) and Mass Spectrometry (MS) detection.

Main Results:

• The developed method demonstrated excellent recoveries in spiked samples, indicating high accuracy.
• Acceptable relative standard deviations (RSDs) were achieved for key validation parameters, ensuring reliability.
• The method proved effective for separating and quantifying lutein and zeaxanthin across food, digesta, and Caco-2 cell matrices.

Conclusions:

• A unified and robust liquid chromatographic method has been established for the accurate quantification of lutein and zeaxanthin.
• The method, incorporating alkaline hydrolysis, offers improved bio-accessibility assessment and is transferable across different sample types.
• This technique provides a valuable tool for high-throughput analysis in nutritional and biomedical research, aiding in understanding carotenoid bioavailability and efficacy.