ABSTRACT
A method was developed for the simultaneous determination of 17 characteristic ingredients of plant extracts, including paeoniflorin, hydroxysafflor yellow A, calycosin_7_glucoside ferulic acid, etc. , in hair growth cosmetics using ultra high performance liquid chromatography ( UPLC ) . Different cosmetic samples were extracted by ultrasonic_assisted extraction with the solvent of methanol/water (4∶1, V/V) solution. After demulsified by the addition of appropriate amount of NaCl and high speed centrifugation, the supernatant was transferred and analyzed with UPLC. The separation was conducted on a Waters reversed phase column of ACQUITY UPLC CSH C18(50 mm×2. 1 mm, 1. 7μm), and the mobile phases were methanol and the solution of 0. 05% phosphate in water. The detection was performed with a photodiode_array ( PDA) detector. The linear range was 0 . 2-25 mg/L with correlation coefficients higher than 0 . 999 . The limits of detection were within 0. 3-1. 5 mg/kg, and the limits of quantification were from 1. 0 to 4. 0 mg/kg. The average recoveries of 17 characteristic ingredients were within 93 . 5%-105 . 0%, with the intra_and inter_day precision ( n=6 ) less than 4. 6%. This method was simple, rapid, with good_repeatability, and had been applied to the analysis of real samples.
ABSTRACT
A method based on stable isotope dilution gas chromatography-mass spectrometry ( GC-MS ) was established to determine five kinds of organophosphate esters ( OPEs ) in different kinds of cosmetics. For cream and wax-based cosmetics, samples were extracted by appropriate solvent, and then purified by ENVI-Carb solid phase extracting column. For powder and aqueous samples, GC-MS test could be operated directly after solvent extraction and concentration. All of the samples were separated by DB-5MS (30 m×0. 25 mm× 0. 25 μm) chromatographic column, and detected by selected ion monitoring ( SIM ) mode. The target analytes were qualitatively confirmed by retention time and abundance ratio of characteristic ions, and quantified by stable isotope diluted internal standard method. Under the optimized conditions, the linear coefficients of the OPEs were larger than 0. 9995, the detection limits were 1. 0-30 μg/kg, the average recoveries ( n=6 ) ranged from 89 . 5% to 105%, and the RSDs were in the range of 2 . 9%-9 . 1%. The developed method, which was characteristic by satisfactory purification effect, favorable matrix effect elimination capacity, as well as high recovery, was suitable for the determination of OPEs in different kinds of cosmetic matrices.