Objective: To find a suitable method for the determination of oxalic acid in the urine of patients with stones, in order to provide a new method and basis for the prevention and treatment of stone. Methods: Liquid chromatography combined with tandem mass spectrometry was used to analyze oxalic acid in urine directly.The accuracy, stability, repeatability and other indicators of the results were tested. Results: The results showed a good linear relationship with the concentration of oxalic acid in urine. y=58.524x-15.246 (R(2)=0.979 02). The results were stable, reproducible (the intra-day and inter-day coefficient of variation was less than 10% and 15%, respectively), and the accuracy was comparable with that of the enzyme method (N=20, R=0.93). Conclusion: Using the method of this study to detect the content of oxalic acid in urine has the advantages of simple operation, good repeatability, accurate results, and low price. It is worth to be popularized and applied in clinical practice.
目的： 寻找合适的方法对结石患者尿中草酸的含量进行测定，以期为开展结石预防及治疗的研究提供方法和依据。 方法： 采用液相色谱－质谱串联技术对尿中草酸含量进行直接分析。并对检测结果的准确性、稳定性、可重复性等指标进行检测。 结果： 检测结果与尿中草酸含量呈良好的线性关系，y＝58.524x－15.246(R(2)＝0.979 02)。结果稳定，具有很好的可重复性。日内、日间变异系数分别小于10%和15%。其准确性与酶法相当(N＝20，R＝0.93)。 结论： 采用本研究方法对尿中草酸含量进行检测，具有操作简便、重复性好、结果准确等优点，值得在临床中推广和应用。.
Keywords: Liquid hromatography tandem mass spectrometry; Oxalic acid; Urinary stone.