Application of a multivariate approach for analyte focusing by micelle collapse‐micellar electrokinetic chromatography for analyzing sunscreen agents in cosmetics

Abstract

The operating parameters that affect the performance of the online preconcentration technique "analyte focusing by micelle collapse-MEKC (AFMC-MEKC)" were examined using a multivariate approach involving experimental design to determine the sunscreen agents in cosmetics. Compared to the single-variable approach, the advantage of the multivariate approach was that many factors could be investigated simultaneously to obtain the best separation condition. A fractional factorial design was used to identify the fewest significant factors in the central composite design (cCD). The cCD was adopted for evaluating the location of the minimum or maximum response in this study. The influences of the experimental variables on the response were investigated by applying a chromatographic exponential function. The optimized condition and the relationship between the experimental variables were acquired using the JMP software. The ANOVA analysis indicated that the Tris pH value, SDS concentration, and ethanol percentage influenced the separation quality and significantly contributed to the model. The optimized condition of the running buffer was 10 mM Tris buffer (pH 9.5) containing 60 mM SDS, 7 mM γ-CD, and 20% v/v ethanol. The sample was prepared in 100 mM Tris buffer (pH 9.0) containing 7.5 mM SDS and 20% v/v ethanol. The SDS concentration in the sample matrix was slightly greater than the CMC value that makes the micelle be easily collapsed and the analytes be accumulated in the capillary. In addition, sunscreen agents in cosmetics after 1000-fold dilution were successfully determined by AFMC-MEKC.

Recent progress of sample stacking in capillary electrophoresis (2014–2016)

“…Table presents other developed methods for the analysis of various environmental samples. A multivariate approach involving experimental design to determine the sunscreen agents in cosmetics examined the operating parameters that affect the performance of online focusing by micelle collapse‐MEKC . Wu et al.…”

Recent advances in enhancing the sensitivity of electrophoresis and electrochromatography in capillaries and microchips (2014–2016)

“…In AFMC , the analytes were neutral UV absorbents , cationic herbicides , neutral pesticides , drugs , vitamins , neurotoxin , amino acid , and sugar . The samples were sunscreen, river water, human blood and urine, and food products.…”

Current trends in sample preparation for cosmetic analysis

“…The ultrasonic bath is the most available and cheap ultrasonic device and allows batch sample treatment. It was often used to extract a wide variety of restricted and banned substances in cosmetics covering all categories of products: makeup powder, eye shadow, lipstick, sunscreen, bleaching cream, lotion, shampoo, soap, and hair dyes [67,71,[120][121][122][123][124][125][126][127][128][129][130][131].…”

“…The choice of extraction solvents strongly depends on physicochemical properties of analytes and cosmetic matrices. Polar solvents such as ethanol, methanol, and ACN are most frequently used for the extraction of organic compounds , while tetrahydrofuran, trichloromethane, and acetone were utilized to improve the solubility of the insoluble matrices (lipstick, eye shadow, and nail products), leading to good extraction efficiency . The degradation of analyte molecules should be taken into account under high‐intensity sonication and long irradiation times, and the duration of 2–30 min was long enough for highly efficient extraction of analytes .…”