建立了高效液相色谱（HPLC）外标定量分析咪唑生产工艺中反应液中咪唑及杂质2-甲基咪唑和4-甲基咪唑含量的方法。在色谱分析中，选用Supersil-ODS-B色谱柱为固定相；选用体积比为40∶60的乙腈-离子对试剂（溶液pH为3.5，内含16 mmol·L^-1十二烷基硫酸钠和17 mmol·L^-1磷酸二氢钾）溶液为流动相进行等度洗脱；采用二极管阵列检测器进行检测，检测波长为210 nm。结果显示：咪唑、2-甲基咪唑及4-甲基咪唑标准曲线的线性范围均为10~100 mg·L^-1，检出限（3S/N）分别为0.02，0.02，0.03 mg·L^-1。咪唑在20 mg·L^-1和100 mg·L^-1添加水平下的平均加标回收率分别为100%，99.2%，相对标准偏差（n=8）为0.27%。用本方法对同一批反应液不同反应阶段的9个样品中咪唑进行了测定，测定值为10.11%~10.71%；杂质2-甲基咪唑有检出，但低于测定下限；杂质4-甲基咪唑未检出。与气相色谱法进行了比对，两者测定结果基本一致。试验结果表明，该方法准确度好、灵敏度高、重现性好，能够准确测定咪唑生产工艺中反应液中咪唑、2-甲基咪唑及4-甲基咪唑的含量。

A HPLC external standard method for quantitative analysis of imidazole and the 2 impurities of 2-methylimidazole and 4-methylimidazole in reaction solutions in the production process of imidazole was established. In the HPLC analysis, Supersil-ODS-B column was selected as stationary phase, and mixture of iacetonitrile and ionic reagent solution (pH 3.5) containing 16 mmol·L^-1 of sodium dodecyl sulfate and 17 mmol·L^-1 of potassium dihydrogen phosphate at a volume ratio of 40:60 was used as mobile phase in isocratict elution. Diode array detector was used for detection, and the detection wavelength was 210 nm. As shown by the results, linearity ranges of standard curves of imidazole, 2-methylimidazole and 4-methylimidazole were same in the range of 10-100 mg·L^-1, and detection limits (3S/N) found was 0.02, 0.02, 0.03 mg·L^-1 respectively. The average recoveries found at the addition levels of 20 mg·L^-1 and 100 mg·L^-1 were 100% and 99.2% respectively, and RSDs (n=8) of the determined values was 0.27%. The imidazole in 9 samples of different reaction stages of the same batch of reaction solution was determined by the present method, giving determined values ranged from 10.11% to 10.71%. The impurity of 2-methylimidazole was detected, but its content was less than the lower limit of determination. 4-methylimidazole was not detected. This method was compared with the gas chromatography method, giving a consistent result. The introduced method was accurate, sensitive and reproducible, which was applied to rapidly determine imidazole, 2-methylimidazole and 4-methylimidazole in the reaction solution in the production process of imidazole.