离子液体作高效液相色谱流动相添加剂测定水杨酸

摘要

A reverse phase high performance liquid chromatographic method was established for the determination of salicylic acid by using ionic liquids as mobile phase additives. The chromatographic separation of salicylic acid was performed on a ZORBAX ODS column ( 250 mm × 4. 6 mm i. d. ,5 μm). The detection of salicylic acid was carried out by ultraviolet(UV) detection. The effects of detection wavelength, pH value, concentration and alkyl chain length of ionic liquids on the separation and determination of salicylic acid were investigated. The optimum chromatographic conditions were as follows: mobile phase: methanol - 3.0 mmol · L- 1 l-butyl-3-methylimidazolium tetrafluoroborate aqueous solution( pH 3.0, adjusted with acetic acid) (60: 40, by volume), UV detection wavelength: 300 nm, flow rate: 1.0 mL · min-1, column temperature: 30 ℃. Under the optimal conditions, the retention time of salicylic acid was about 4. 4 min. The calibration curve showed a good linearity over the range of 2 - 100 mg · L-1 for salicylic acid with a correlation coefficient of 0. 999 9. The detection limit was 0. 059 mg/L. The average spiked recovery was 100％ with relative standard deviation of 0. 11％. The method was successfully applied in the determination of the content of salicylic acid in the pharmaceutical of Zujunqing Tinctura.%建立了以离子液体作反相高效液相色谱流动相添加剂测定水杨酸的方法.实验以ZORBAX ODS反相色谱柱为分离柱,采用紫外检测方法,研究了检测波长、离子液体烷基链长度、离子液体溶液的浓度以及pH值等对分离和测定的影响.优化的色谱条件为:以体积比60:40的甲醇-3.0 mmol/L1-丁基-3-甲基咪唑四氟硼酸盐溶液(乙酸调pH 3.0)为流动相;检测波长300 nm;流速1.0 mL/min;进样体积20μL;柱温30℃.在该优化条件下,水杨酸的保留时间约为4.4 min,检出限为0.059 mg/L,标准曲线在2～100 mg/L范围内线性关系良好(r=0.999 9).方法的平均加标回收率为100%,相对标准偏差为0.11%.将方法应用于足菌清酊剂药品的分析,结果满意.