[Quantitative measurement of citric acid in urine using tandem liquid chromatography mass spectrometry].

Objective: To find a suitable method for the determination of citric 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 tandem mass spectrometry was used to analyze the citric acid in urine directly. And the accuracy, stability, repeatability and other indicators of the results were detected. Results: The results showed a good linear relationship with the concentration of citric acid in urine. y=50.31x+ 0.002 6 (R(2)=0.994 21). The results were stable, reproducible [intra-day (Coefficient of Variance) CV ≈1% and inter-day CV<10%], and the accuracy of which was comparable with that of the enzyme method (n=20, R=0.97). Conclusion: Using the method of this study to detect the content of citric acid in urine has the advantages of simple operation, good repeatability, accurate results, and low price. So 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枸橼酸的含量进行测定，以期为开展结石预防及治疗的研究提供新的方法和依据。 方法： 采用液相色谱－质谱串联技术对尿中枸橼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： 检测结果与尿中枸橼酸含量呈良好的线性关系，y＝50.31x＋0.002 6(R(2)＝0.994 21)，结果稳定，具有很好的可重复性。日内变异系数约为1%，日间变异系数<10%。其准确性与酶法相当(n＝20，R＝0.97)。 结论： 采用本研究方法对尿中枸橼酸含量进行检测，具有操作简便、重复性好、结果准确等优点，且较酶法价格低廉，值得在临床中推广和应用。.