| Summary: | 碩士 === 靜宜大學 === 化粧品科學系 === 104 === This study is to propose a novel method for determination regulations limits used sebum softener, such as Mandelic Acid,Salicylic acid and Resorcinol on detection in cosmetics. For this purpose, a fastly and convenient analytical instrument Capillary Electrophorsis (CE) combine with Dispersive liquid-liquid micro extraction (DLLME) was designed, and this parameters were studied by orthogonal experimental design and statistical analysis to optimize. The Taguchi Method was applied to at L16(215) and L18 (21×37) orthogonal experimental design.
According to the number of chromatographic peaks, peak signal strength and retention time, separation voltage at -25 kV and a background electrolyte(BGE, 10 mM phosphate buffer at pH 9) were used. Sebum softeners in cosmetics were analyzed by CE at 220 nm. For measured in quantifying the collected solvent, the present work utilizes a self-designed glass tube in the extraction process. The optimum parameters for MA, SA and Res were investigated.
Parameters influencing the extraction efficiency of DLLME-BE-CE, such as the extraction and dispersive solvent, solvent volume, and salt-addition were thoroughly investigated and optimized. After that, the maximum extraction efficiency was obtained by loading 20 µL 10mM HCl 3 mL sample solution, by the addition of 200 μL Octanol (extractant) and 80 μL Acetonitrile. Then the device was sealed with parafilm, and the cloudy solution was centrifuged at 3000 rpm for 3min and the separated extractant was injected directly into CE for analysis.
By the ANOVA(analysis of variance),we can find the parameters which influence the extraction solvent type and the optimum combination of parameter values. Under the selected conditions,determination of sebum softeners ranged in 10-2000 ng/mL. The coefficient of determination were obtained above 0.9935. Detection limits were achieved at the level of 0.5-6.7 ng/mL. Quantitative limits were achieved at the level of 2.7-18.4 ng/mL. The relative standard deviations of intra-day and inter-day precisions were 4.58-8.44 % and 7.35-15.68 %. The extraction time was less than 10 minutes.
The results demonstrated that the proposed DLLME-BE-CE method provides a simple, rapid, inexpensive, convenient, eco-friendly and less matrix interferences process for the determination sebum softener in cosmetic samples.
|
|---|
