# Bioactive Lipophilic Antioxidants (Carotenoids, Tocols, Retinol, and Coenzyme Q10) in Human and Animal Tissues: Development and Validation of a Rapid Extraction and Chromatographic Method for Nutrition and Health Studies

## TL;DR

The paper introduces a fast and reliable method to measure antioxidants like carotenoids and coenzyme Q10 in human and animal tissues, aiding nutrition and health research.

## Contribution

A new rapid extraction and chromatographic method for quantifying multiple lipophilic antioxidants in tissues is developed and validated.

## Key findings

- The method successfully identified 38 compounds with high recovery rates and precision for most analytes.
- Colorless carotenoid isomers were detected in human tissues for the first time.
- The method is versatile and reliable for analyzing antioxidant levels in various tissue types.

## Abstract

A rapid and robust analytical method was validated for the simultaneous extraction and quantification of carotenoids and other lipophilic antioxidants (tocopherols, tocotrienols, retinol and coenzyme Q10) in human and animal tissues using a tandem RRLC-DAD-FLD system. Thirty-eight compounds were identified, with limits of quantification as low as 0.001 µg for astaxanthin, retinol, and coenzyme Q10. Most analytes exhibited high recoveries (85–94%) and good precision (coefficient of variation < 10%), except for Co-Q10, which showed moderate variability. The method was applied to seven human tissue types and their corresponding animal tissues, demonstrating high versatility and analytical reliability. Several isomers of colourless carotenoids were identified in human tissues for the first time, reinforcing their emerging relevance in photoprotection and health. This method provides a valuable analytical tool for investigating the tissue distribution, bioavailability, functionality and nutritional significance of lipophilic antioxidants, thereby supporting future research on antioxidant status and health-related actions.