Method for separating and determining 1,2-propylene glycol enantiomers by using gas chromatography

The invention discloses a method for separating and determining 1,2-propylene glycol, bulk drugs containing 1,2-propylene glycol and 1,2-propylene glycol enantiomer impurities in preparations of the bulk drugs by using precolumn derivatization gas chromatography. The method employs an aldehyde ketone compound as a derivative reagent, carries out precolumn derivatization on the aldehyde ketone compound and 1,2-propylene glycol in the presence of a catalyst and a water reducer and determines trace enantiomer impurities by using gas chromatography. The method provided by the invention overcomes the defect of incapability of accurate quantification of 1,2-propylene glycol enantiomer impurities due to serious trailing of peaks during frequently-used chiral gas chromatographic column separation and guarantees that the quality of 1,2-propylene glycol, the bulk drugs containing 1,2-propylene glycol and the preparations thereof is controllable.