Hassan S S, Rizk N M
Department of Chemistry, Faculty of Science, Ain Shams University, Cairo, Egypt.
Analyst. 1997 Aug;122(8):815-9. doi: 10.1039/a701038i.
Miniaturized poly(vinyl chloride) matrix membrane sensors in an all-solid-state graphite support, responsive to urate anion, were developed. The membranes incorporate lipophilic ion-pair complexes of urate anion with ruthenium(III), iron(II), nickel(II) and copper(I) bathophenanthroline (4,7-diphenyl-1,10-phenanthroline) counter cations. The sensors demonstrate a near-Nernstian response to urate over the concentration range 1 x 10(-2)-1 x 10(-5) mol l-1 and have micromolar detection limits and good selectivity properties. The response is virtually unaffected by pH changes in the range 7-10 and the response times are 5-10 s in aqueous solutions and in human serum and urine samples. A flow injection detector incorporating an iron(II) bathophenanthroline-urate graphite sensor was used for continuous monitoring of uric acid. The minimum detectable concentration was approximately 8 micrograms ml-1 and the sample throughput was approximately 120 h-1. Direct potentiometric determination of uric acid in the static and hydrodynamic modes of operation over the range 15 micrograms ml-1-1.5 mg ml-1 showed average recoveries of 98.7 and 97.8% with RSDs of 0.6 and 0.7%, respectively. Application of the method to the determination of uric acid in human serum and urine gave results that compared favourably with those obtained by the standard spectrophotometric method.
开发了一种全固态石墨支撑的小型聚氯乙烯基质膜传感器，该传感器对尿酸根阴离子有响应。这些膜包含尿酸根阴离子与钌（III）、铁（II）、镍（II）和铜（I）邻菲啰啉（4,7-二苯基-1,10-菲啰啉）抗衡阳离子形成的亲脂性离子对配合物。该传感器在1×10⁻² - 1×10⁻⁵ mol l⁻¹的浓度范围内对尿酸根表现出近能斯特响应，具有微摩尔检测限和良好的选择性。在7 - 10的pH范围内，响应几乎不受pH变化的影响，在水溶液、人血清和尿液样本中的响应时间为5 - 10秒。使用包含铁（II）邻菲啰啉 - 尿酸根石墨传感器的流动注射检测器对尿酸进行连续监测。最低检测浓度约为8微克/毫升，样品通量约为120次/小时。在15微克/毫升 - 1.5毫克/毫升范围内，以静态和流体动力学操作模式直接电位法测定尿酸，平均回收率分别为98.7%和97.8%，相对标准偏差分别为0.6%和0.7%。将该方法应用于人血清和尿液中尿酸的测定，所得结果与标准分光光度法获得的结果相比具有优势。
