利用高效液相層析法定量防曬劑中OXYBENZON及OCTYL DIMETHYL PABA成分

ANALYSIS OF OXYBENZONE AND OCTYL DIMETHYL PABA ON COSMETIC PRODUCTS BY HPLC

本研究發展一簡單、精確、快速的逆相高效液相層析法，同時分離及定量防曬劑中Oxybenzone （I） 及Octyl dimethyl PABA （II） 二成分。Eusolex 6300被用作內部標準品，使用之層析管含Inertsil ODS-2 （5μm,4.6mm I.D.x15cm不鋼管），移動相為Acetonitrile：水（85：15），測定波長為UV 280nm。系統適用性測試結果，重複注射二成分之c.v。值不超過0.76%（I）及0.51%（II）；所得標準曲線之線性關條良好，r值分別為0.9998 （I） 及0.9999 （II） 回收率實驗之分離效果亦佳，實驗結果均在99.6%～100.4% （I） 及100.4%～102.0% （II） 之間。另就不同劑型不同SPF之市售產品8件，應用此法作定量分析，由其層析圖譜顯示，分離效果如預期之理想，各檢體之含量亦皆符合90.0%～110.0%規定。本法在10分鐘內即可定量完畢，現已成功地應用於本局例行案件之檢驗。

A simple isocratic, high-performance liquid chromatographic (HPLC) assay proposed for the simultaneous determination of Oxybenzone (I) and Octyl dimethyl PABA (II) in sunscreens, using Eusolex 6300 as an internal standard. Sunscreens samples were extracted by direct dissolution in ethanol. all standards were dissolved by ethanol. The chromatographic conditions included: flow rate= 1.0 ml/min; Inertsil ODS-2 column (5um, 4.6mm I.D. x15 cm); 280nm UV detector. The results of system suitability tests were as follows: the coefficients of variation were less than 0. 76% and 0.51% for (I) and (II) respectively; the correlation coefficients were 0.9998 (I) and (II) respectively; the correlation coefficients were 0.9998 (I) and 0.9999 (II). Recovery experiments gave 99.6%-100.4% for (I) and 100.1%-102.0% for (II). the method can be used for the determination of commercial products and has been applied for the routine analysis in our Laboratory.