Analysis of benzophenones in environmental water samples after topical skin application using dispersive liquid-liquid microextraction and micellar electrokinetic capillary chromatography

Dispersive liquid-liquid microextraction (DLLME) was developed for MEKC determination of 2,4-dihydroxy-benzophenone (HBP) and 2-hydroxy-4-methoxy-benzophenone (HMBP) in environmental water samples after topical skin application. Parameters affecting the extraction efficiency were investigated in detail. Under the optimum conditions, enrichment factors (EFs) of 208.9 for HBP and 194.6 fold for HMBP were obtained. The detection limits are 0.52 mmol L(-1) HBP and 0.29 mmol L(-1) HMBP, and the precisions for eight replicate measurements of 5.0 mmol L(-1) of HBP and HMBP are 4.9% and 1.5%, respectively. Environmental water samples after topical skin application were successfully analyzed by the proposed method with satisfactory results.