ABSTRACT
Objective: To develop an HPLC method for the simultaneous determination of 3 ultraviolet absorbers (benzylidene camphor sulfonic acid, camphor benzalkonium methosulfate, 4-methylbenzylidene camphor) in cosmetics.Methods: After extracted by acetonitrile-methanol-ammonium acetate aqueous solution-tetrahydrofur(30∶35∶30∶5, v/v)(for lotion and milk) or acetonitrile-methanol-ammonium acetate aqueous solution(30∶20∶50, v/v)(for cream and powder), the UV absorbers were separated on a Thermo scientific C18 column (250 mm×4.6 mm,5 μm) at 35 ℃ with methanol, acetonitrile and 0.02 mol·L-1ammonium acetate aqueous solution (pH 5.15 adjusted by glacial acetic acid) as the mobile phase with gradient elution at the flow rate of 1.0 ml·min-1, and then analyzed by a DAD detector at the wavelength of 288 nm and 300 nm.Results: Benzylidene camphor sulfonic acid, camphor benzalkonium methosulfate and 4-methylbenzylidene camphor showed good linearity within the range of 12.26-98.06 μg·ml-1(r=0.999 9), 9.31-74.48 μg·ml-1(r=0.999 9) and 6.86-54.88 μg·ml-1(r=0.999 9), respectively.The limit of detection (LOD) and the limit of quantitation (LOQ) were 4.6, 6.4 and 1.6 ng and 17.4, 15.9 and 5.5 ng, respectively.The average recovery was 99.2%(RSD=1.58%), 99.8%(RSD=2.38%) and 99.2%(RSD=2.03%)(n=36), respectively.Conclusion: The method is simple, rapid, reproducible, accurate and reliable, and can be applied in the determination of ultraviolet absorbers in cosmetics.
ABSTRACT
Objective To obtain two types of optical isomers from 1-(Benzamidomethyl)-1,2,3,4-tetrahydro-isoquinoline (BTIQ). Methods ( ±) BTIQ as raw materials , optically pure camphor sulfonic acid as resolution agent was used and repeated resolution in acetone , And the resolution product was detected by specific optical rotation .The product of BTIQ was hydrolyzed , and the ratio of ATIQ was compared with that of the literature .ResuIts After two repeated chemical resolutions , the specific rotations of both enantiomers are no longer changed .It was showed that the products of higher optical purity.The specific rotation of both isomers are -35.65°(CH2Cl2, C=0.5)with the yield of 27.52%,and +35.17°(CH2Cl2, C =0.5) with the yield of 31.55% respectively.The specific rotation value of chiral 1,2,3,4-tetrahydroisoquino line ( ATIQ) which was the hydrolysis product of BTIQ consistent with values reported in the literature .ConcIusion The (-) BTIQ and ( +) BTIQ enantiomers were successfully obtained by the method of resolution , and the yield and optical purity of the obtained products are higher , laying the foundation for the further development of high efficiency , low toxicity of chiral schistosomicide ( praziquantel ) and other containing tetrahydroisoquinoline structure of chiral drugs .