Determination of benzophenones in a cosmetic matrix by supercritical fluid extraction and capillary electrophoresis.
Benzophenones are common additives in commercial sunscreen products. These UV absorbers were extracted by supercritical fluid extraction (SFE), and then analyzed by capillary zone electrophoresis (CZE) and high-performance liquid chromatography. This study was applied to identify the contents of benzophenones in cosmetic matrix, and simultaneously, to investigate the behavior of migration in CZE. Adding non-ionic surfactant (Tween 20) to optimize the separation in the CZE operation improves resolution. In SFE, we chose carbon dioxide with 2.5% modifier of 10% aqueous phosphoric acid-MeOH (1:1) as the supercritical fluid. Real recoveries of up to 92% with relative standard deviations of less than 4.0% were achieved. These analytical techniques were also applied to assay benzophenones for ten commercial sunscreen cosmetics. We found benzophenone 3 was the most commonly used sunscreen additive in Taiwan.
Wang
Shu-Ping
SP
Department of Applied Chemistry, Providence University, 200 Chungchi Road, Shalu, Taichung, Hsien 43301, Taiwan. spwang@pu.edu.tw
Lee
Wen-Tsong
WT
D001577:Benzophenones / Q000032:analysis*; D025924:Chromatography, Supercritical Fluid / Q000379:methods*; D019075:Electrophoresis, Capillary / Q000379:methods*; D013473:Sunscreening Agents / Q000737:chemistry*
D001577:Benzophenones; D013473:Sunscreening Agents