高效液相色谱法测定尿中甲基马尿酸的规范化研究

Standardized study on the determination of methylhippuric acids in urine by HPLC

目的:完善和规范化二甲苯接触者尿中甲基马尿酸的高效液相色谱测定法,较好地分离甲基马尿酸的3种同分异构体。方法:采用waters反相C18柱,以甲醇+0.1%冰乙酸(33+67)为流动相,流速为0.7 ml/min,波长为230 nm。结果:甲基马尿酸的3种同分异构体在25μg/ml～1000μg/ml范围内线性良好,相关系数r为0.9995～0.9996,相对标准偏差为2.0%～9.6%,加标回收率为91.36%～101.36%,2-甲基马尿酸、3-甲基马尿酸和4-甲基马尿酸的最低检测浓度分别为0.47μg/ml、0.46μg/ml、0.41μg/ml;3-甲基马尿酸和4-甲基马尿酸的分离度达到要求。结论:该方法能够使3-甲基马尿酸和4-甲基马尿酸达到分离,方法学各项指标均符合职业卫生标准制定指南第五部分-生物材料中化学物质测定方法的相关要求,可用于职业接触二甲苯人群尿中甲基马尿酸的测定。

Objective：To get a better separation of methylhippuric acid isomers and establish a standardized method for the determination of methylhippuric acids in urine by HPLC. Methods： C18 column was used to determine the methylhippuric acid. The mobile phase was Methanol - 0.1% acetic acid （33： 67）. The detector was performed at k = 230 nm, at 0.7 ml/min. Results： Calibration curves of three methylhippuric acids were linear in the range of 25μg/ml - 1000 μg/ml, with a correlation coefficient more than 0. 999. The average recovery was in the range of 91.36% - 101.36% and the average RSD was in the range of 2.0% -9.6%. The minimum detection concentrations of 2 - MHA, 3 - MHA, 4 - MHA were respectively 0.47 μg/ml, 0.46 μxg/ml, 0.41 μg/ml. The separation of 4 - methyhippuric acid and 3 - methyhippuric acid was up to 1.44. Conclusion： The method is able to make 3 - methylhippuric acid and 4 - methylhippuric acid baseline separated, and the methodology indicators are in line with the relevant requirements of the method for determination of chemicals in the occupational health standard -setting Guide Part V. So it can be used to determine methylhippuric acids in urine of xylenes exposure workers.