Zhang Ya, Zheng Jianbin
Institute of Analytical Science/Shaanxi Provincial Key Lab of Electroanalytical Chemistry, Northwest University, Xi'an, Shaanxi 710069, China.
Talanta. 2008 Oct 19;77(1):325-30. doi: 10.1016/j.talanta.2008.06.032. Epub 2008 Jul 1.
An ionic liquid modified carbon paste electrode (IL/CPE) had been fabricated by using hydrophilic ionic liquid 1-amyl-3-methylimidazolium bromide ([AMIM]Br) as a modifier. The IL/CPE was characterized by scanning electron microscope and voltammetry. Electrochemical behavior of rutin at the IL/CPE had been investigated in pH 3.29 Britton-Robinson (B-R) buffer solution by cyclic voltammetry (CV) and square wave voltammetry (SWV). The experimental results suggested that the modified electrode exhibited an electrocatalytic activity toward the redox of rutin. The electron transfer coefficient (alpha) and the standard rate constant (k(s)) of rutin at the modified electrode were calculated. Under the selected conditions, the reduction peak current was linearly dependent on the concentration of rutin in the range of 4.0x10(-8) to 1.0x10(-5)mol L(-1) (r=0.9998), with a detection limit of 1.0x10(-8)mol L(-1)(S/N=3). The relative standard deviation (R.S.D.) for six times successful determination of 8.0x10(-7)mol L(-1) rutin was 1.2%. The proposed method was applied to determine rutin in tablet and urine sample. In addition, the IL/CPE exhibited a distinct advantage of simple preparation, surface renewal, good reproducibility and good stability.
采用亲水性离子液体1-戊基-3-甲基咪唑溴盐（[AMIM]Br）作为修饰剂制备了离子液体修饰碳糊电极（IL/CPE）。通过扫描电子显微镜和伏安法对IL/CPE进行了表征。采用循环伏安法（CV）和方波伏安法（SWV）研究了芦丁在pH 3.29的Britton-Robinson（B-R）缓冲溶液中在IL/CPE上的电化学行为。实验结果表明，修饰电极对芦丁的氧化还原反应具有电催化活性。计算了芦丁在修饰电极上的电子转移系数（α）和标准速率常数（k(s)）。在选定的条件下，还原峰电流在4.0×10(-8)至1.0×10(-5)mol L(-1)范围内与芦丁浓度呈线性关系（r = 0.9998），检测限为1.0×10(-8)mol L(-1)（S/N = 3）。对8.0×10(-7)mol L(-1)芦丁进行六次成功测定的相对标准偏差（R.S.D.）为1.2%。该方法已应用于片剂和尿液样品中芦丁的测定。此外，IL/CPE具有制备简单、表面可更新、重现性好和稳定性好等明显优点。
