建立了反相高效液相色谱-质谱法测定三乙醇胺酯季铵盐中单、双、三酯季铵盐的方法。样品经过乙醚萃取3次,所得提取液在50 ℃水浴中蒸干,用正丙醇溶解后进样10 μL。用CN-3氰基柱作固定相,用不同比例的正丙醇与水的混合溶液作流动相进行梯度淋洗,质谱测定中采用电喷雾电离-正离子模式及多反应监测模式,以峰面积归一化法定量。结果表明:三乙醇胺单、双、三酯季铵盐线性范围为0.25~7.5 mg·L-1,检出限(3S/N)依次为0.08,0.10,0.10 mg·L-1。对方法进行精密度试验,测得相对标准偏差(n=6)分别为10.9%,8.3%,3.8%。

Quaternary ammonium salts of mono-, di-and tri-esters of trihydroxyethylamine were separated and determined by RP-HPLC-MS. The sample was extracted thrice with ethylether, and the extracts were combined and evaporated to dryness at 50 ℃ in a water bath. The residue was dissolved with n-propanol, and the solution obtained was used for RP-HPLC-MS analysis, with 10 μL aliquot for sample introduction. DIKMA Inertsil CN-3 column was used as stationary phase and mixtures of n-propanol and water with different ratios were used as mobile phase in the gradient elution. Changed aerosol ionization with positive ion mode and MRM mode were used in MS analysis. Normalization of peak area was adopted in the determination. Linear relationship between values of lgA (A represents the peak area) and mass concentration of quaternary ammonium salts of mono-, di- and tri-ester of trihydroxyethylamine were found in the same range of 0.25-7.5 mg·L-1, with detection limits (3S/N) of 0.08, 0.10, 0.10 mg·L-1 respectively. Precision of the method was tested, values of RSD′s (n=6) found for the 3 quaternary ammonium salts were 10.9%, 8.3% and 3.8% respectively.