Validated TLC–Densitometric and UV–Vis Methods for Fucoxanthin Determination in Sargassum ilicifolium

Abstract

Fucoxanthin, the principal carotenoid pigment in Sargassum ilicifolium, possesses a distinct orange hue that makes it a promising natural compound for pharmaceutical, cosmetic, and food applications. This study aimed to develop and validate simple, accurate, and cost-effective analytical methods for fucoxanthin determination using UV–Vis spectrophotometry and TLC–densitometry. The measurements were conducted at wavelengths of 445 nm (UV–Vis) and 366 nm (TLC–densitometry). The methods demonstrated excellent linearity with correlation coefficients (r) of 0.9981 and 0.9887 within concentration ranges of 0.25–2.5 µg/mL and 0.5–40 µg/mL, respectively. The limits of detection (LOD) and quantification (LOQ) were 0.17 µg/mL and 0.52 µg/mL for UV–Vis, and 2.5 µg/mL and 7.5 µg/mL for TLC–densitometry. Recovery values ranged from 95.07–98.06% (UV–Vis) and 100.50–102.00% (TLC–densitometry), with RSD values below 1%, fulfilling ICH and AOAC validation criteria. These validated methods provide reliable and accessible alternatives to advanced instrumentation, supporting fucoxanthin analysis in phytopharmaceutical research and quality control.