顶空-气相色谱法测定尿中TCA方法的改进

Improved method for determination of TCA in urine by headspace-gas chromatography

目的测定尿中三氯乙酸(trichloroacetic acid,TCA)顶空-气相色谱法的改进。方法取一定体积的尿液加入0.5 mL10%乙酸钠溶液密封于22 mL顶空瓶中,通过自动顶空仪加热脱羧生成的三氯甲烷直接进入气相色谱仪进行检测分析。结果使用HP-INNWAX色谱柱可以有效进行尿中TCA的检测分析,当在尿样中加入0.5 mL 10%的乙酸钠时,顶空仪90℃平衡60 min是最佳脱羧条件,在0.5~50.0μg质量范围内相关系数r=0.9992。结论该法将脱羧反应设计于顶空装置中,操作简单便捷,有效减少反应时间和人力消耗,提高了工作效率;在脱羧反应中加入乙酸钠溶液,增加了TCA检测的稳定性和灵敏度。

Objective To improve the method the determination of trichloroacetic acid(TCA)in urine by headspace-gas chromatography.Methods 0.5 mL 10%sodium acetate solution was added into a certain volume of urine and sealed in a 22 m L headspace bottle,trichloromethane was generated by decarboxylation by heating with an automatic headspace apparatus,and directly analyzed and detected by the gas chromatograph.Results HP-INNWAX column can be used for the detection and analysis of TCA in urine effectively.When 0.5 mL 10%sodium acetate was added into the urine samples,the best decarboxylation condition was that the headspace instrument was equilibrated at 90℃for 60 min,and the correlation coefficient was(r)0.9992 in the mass range of 0.5-50.0μg.Conclusion When the decarboxylation reaction is designed in the headspace device,the operation is simple and convenient,which effectively reduce reaction time and labor consumption,and improve work efficiency,at the same time,the stability and sensitivity of TCA determination is improved by adding sodium acetate solution in decarboxylation reaction.