Abstract
ntroduction: Retinoic acid is a prescription-only vitamin A derivative prohibited as a cosmetic ingredient under Indonesian FDA Regulation No. 17 of 2022, yet it may still be present in unregistered facial lightening creams. This study aimed to validate a UV-Vis spectrophotometric method and determine the presence and level of retinoic acid in facial whitening creams marketed in Bengkulu City. Method: Five products were purposively collected from Panorama Market and Minggu Market. Preliminary identification used antimony(III) chloride (SbCl3) color reaction and thin-layer chromatography (TLC), while quantitative determination used UV-Vis spectrophotometry. Validation covered linearity, precision, accuracy, limit of detection (LOD), and limit of quantitation (LOQ). Result and Discussion: Samples C and D were positive by color reaction and TLC, showing an Rf of 0.89 compared with 0.86 for the reference standard, whereas samples A, B, and E were negative. The maximum wavelength was 341 nm. R² values from three linearity replications were 0.99832, 0.99137, and 0.99592; precision was 3.14% RSD; recovery ranged from 97.39% to 103.53%; LOD and LOQ were 0.1546 and 0.4686 ppm, respectively. Mean retinoic acid levels in samples C and D were 0.00072% and 0.0020%. Conclusion: Retinoic acid was detected in part of the tested products. The method showed acceptable precision and accuracy, although sample concentration estimates require cautious interpretation because the regression-derived concentrations were below the LOQ.