Department of Chemistry and Environmental Research Center, Missouri University of Science and Technology, Rolla, MO 65409, USA.
Anal Bioanal Chem. 2012 Jan;402(2):763-70. doi: 10.1007/s00216-011-5491-4. Epub 2011 Oct 27.
Current urinary bladder cancer diagnosis is commonly based on a biopsy obtained during cystoscopy. This invasive method causes discomfort and pain in patients. Recently, taurine and several other compounds such as L-phenylalanine and hippuric acid in urine were found to be indicators of bladder cancer. However, because of a lack of sensitive and accurate analytical techniques, it is impossible to detect these compounds in urine at low levels. In this study, using liquid chromatography-tandem mass spectrometry (LC-MS/MS), a noninvasive method was developed to separate and detect these compounds in urine. (15)N(2)-L-glutamine was used as the internal standard, and creatinine acted as an indicator for urine dilution. A phenyl-hexyl column was used for the separation at an isocratic condition of 0.2% formic acid in water and 0.2% formic acid in methanol. Analytes were detected in multiple-reaction monitoring with positive ionization mode. The limit of detection range is 0.18-6 nM and the limit of quantitation ranges from 0.6 to 17.6 nM. The parameters affecting separation and quantification were also investigated and optimized. Proper clinical validation of these biomarkers can be done using this reliable, fast, and simple method. Furthermore, with simple modifications, this method could be applied to other physiological fluids and other types of diseases.
目前膀胱癌的诊断通常基于膀胱镜检查时获得的活检。这种侵入性方法会给患者带来不适和疼痛。最近，发现牛磺酸和尿液中的其他几种化合物，如 L-苯丙氨酸和马尿酸，是膀胱癌的指标。然而，由于缺乏敏感和准确的分析技术，无法在低水平下检测到尿液中的这些化合物。在这项研究中，使用液相色谱-串联质谱法 (LC-MS/MS)，开发了一种非侵入性方法来分离和检测尿液中的这些化合物。（15）N(2)-L-谷氨酰胺被用作内标，而肌酸则作为尿液稀释的指示剂。在等度条件下，使用苯基-己基柱，以水和甲醇中的 0.2%甲酸作为分离条件。在正离子模式下进行多反应监测检测分析物。检测限范围为 0.18-6 nM，定量限范围为 0.6-17.6 nM。还研究和优化了影响分离和定量的参数。使用这种可靠、快速和简单的方法可以对这些生物标志物进行适当的临床验证。此外，通过简单的修改，该方法可以应用于其他生理液和其他类型的疾病。
