A capillary electrophoresis(CE) method was established for the simultaneous separation and determination of seven preservatives in cosmetics

including methyl p hydroxybenzoate

ethyl p-hydroxybenzoate

propyl p hydroxybenzoate

butyl p hydroxybenzoate

chlorophenylglycol

octanoyl valerate and sodium dehydroacetate.Effects of different electrophoresis conditions

including type and concentration of additive

pH value of the running buffer and separation voltage on separation were investigated.The optimal conditions were follows:additive:10 mmol/L sulfobutyl-β-cyclodextrin

buffer:pH 8.0 20 mmol/L phosphate buffer

separate voltage:20 kV

detection wavelength:280 nm.Results showed that

under the optimal conditions

seven preservatives could reach the baseline separation within 5 min.The calibration curves were linear in the concentration range of 5-200 mg/L

with correlation coefficients(r) of 0.990 7-0998 9.The detection limits were in the range of 123-430 mg/L

and the relative standard deviations(RSD) for migration time were not more than 1.3%.Average recoveries for the spiked samples were in the range of 95.4%-103%.The method is accurate

simple

efficient and practical

and could be applied in the determination of seven preservatives in actual samples.