Jiangsu Key Laboratory of Biofunctional Materials, Laboratory of Electrochemistry, College of Chemistry and Environmental Science, Nanjing Normal University, Nanjing 210046, People's Republic of China.
Anal Chem. 2010 Mar 15;82(6):2448-55. doi: 10.1021/ac9028246.
This work develops and validates an electrochemical approach for uric acid (UA) determinations in both endogenous (cell lysate) and physiological (serum) samples. This approach is based on the electrocatalytic reduction of enzymatically generated H(2)O(2) at the biosensor of uricase-thionine-single-walled carbon nanotube/glassy carbon (UOx-Th-SWNTs/GC) with the use of Th-SWNTs nanostructure as a mediator and an enzyme immobilization matrix. The biosensor, which was fabricated by immobilizing UOx on the surface of Th-SWNTs, exhibited a rapid response (ca. 2 s), a low detection limit (0.5 +/- 0.05 microM), a wide linear range (2 microM to 2 mM), high sensitivity (approximately 90 microA mM(-1) cm(-2)), as well as good stability and repeatability. In addition, the common interfering species, such as ascorbic acid, 3,4-dihydroxyphenylacetic acid, 4-acetamidophenol, etc., did not cause any interference due to the use of a low operating potential (-400 mV vs saturated calomel electrode). Therefore, this work has demonstrated a simple and effective sensing platform for selective detection of UA in the physiological levels. In particular, the developed approach could be very important and useful to determine the relative role of endogenous and physiological UA in various conditions such as hypertension and cardiovascular disease.
这项工作开发并验证了一种电化学方法，用于测定内源性（细胞裂解液）和生理（血清）样品中的尿酸（UA）。该方法基于尿酸酶-硫代-单壁碳纳米管/玻碳（UOx-Th-SWNTs/GC）生物传感器上电催化还原酶促生成的 H(2)O(2)，使用 Th-SWNTs 纳米结构作为介体和酶固定基质。该生物传感器通过将 UOx 固定在 Th-SWNTs 表面制备而成，具有快速响应（约 2 s）、低检测限（0.5 +/- 0.05 microM）、宽线性范围（2 microM 至 2 mM）、高灵敏度（约 90 microA mM(-1) cm(-2)）以及良好的稳定性和重现性。此外，由于使用了低工作电位（-400 mV 对饱和甘汞电极），常见的干扰物质，如抗坏血酸、3,4-二羟基苯乙酸、4-乙酰氨基酚等，不会引起任何干扰。因此，这项工作展示了一种用于选择性检测生理水平下 UA 的简单有效的传感平台。特别是，所开发的方法对于确定内源性和生理 UA 在高血压和心血管疾病等各种情况下的相对作用可能非常重要和有用。
