Aim:To develop an HPCE method for the chiral separation of dopa methyl ester hydrochloride enantiomers.Methods:The enantiomers were separated by HPCE on a capillary of 63.5/72.0(I/L)cm×50 μm(i.d) with the background electrolyte of 20 mmol/L sodium dihydrogen phosphate,which containing 2.5% of highly sulfated-β-cyclodextrin as the chiral resolving additive adjusted to pH 2.55 with phosphoric acid.The outlet pressure injection mode and positive voltage of 30 kV electric force were used with the cassette temperature at 25 ℃ and UV detection at 210 nm.Attempts were made to optimized the separation conditions.Results:The enantiomers were baseline separated at the optimized conditions with the resolution greater than 2.The calibration curve was linear for L-dopa methyl ester hydrochloride in the range from 10 to 4 000 μg/mL using aminobenzoic acid as internal standard.And the limit of detection was 2.0 μg/mL.Conclusion:The established HPCE method is of high performance and economy for the chiral separation.It could be used as the routine method for the chiral purity analysis of L-dopa methyl ester hydrochloride.
