柱前衍生化-非水毛细管电泳法高效分离饮料中的脂肪醛

以9,10-菲醌作为柱前衍生试剂,采用非水毛细管电泳模式考察并优化了脂肪醛的分离条件。实验采用毛细管(总长58.5 cm,有效长度50 cm,内径50 μm),应用80 mmol/L NH4Ac、1.4 mol/L HAc缓冲体系,于20 ℃、5 kPa(50 mbar)下压力进样 8 s,在不加入其他添加剂的情况下,实现了7种脂肪醛的高效基线分离,检出限为0.37～0.87 μmol/L,线性范围为0.78～25 μmol/L。应用所建立的方法对实际样品进行了测定,结果令人满意。

Separation of derivatized aliphatic aldehydes in beverage by nonaqueous capillary electrophoresis

A simple and mild method for the separation of aliphatic aldehydes based on a condensation reaction with 9,10-phenanthrenequinone as labeling reagent with nonaqueous capillary electrophoresis has been developed. The detection was performed with a diode array detector (DAD). A 58.5 cm (50 cm effective length)×50 μm i. d. untreated fused-silica capillary was used. To optimize the conditions, the background electrolyte concentration, column temperature, voltage and other factors were evaluated. The results indicated that the buffer concentration had a great impact on the separation, but the influences of temperature and added additives on the resolution were not obvious. The optimized conditions were as follows: 80 mmol/L ammonium acetate, 1.4 mol/L acetic acid, voltage of 28 kV, column temperature of 20 ℃ and DAD detection at 254 nm. The samples were introduced atmospherically with the injection at 5 kPa (50 mbar) for 8 s. The results indicate that seven aliphatic aldehyde derivatives and actual samples can be achieved baseline resolution under the proposed conditions.