差分脉冲伏安法间接检测氯吡脲

Indirect determination of forchlorfenuron using differential pulse voltammetry

氯吡脲可以抑制铁氰化钾的还原反应,基于此建立了差分脉冲伏安法(DPV)间接测定氯吡脲浓度的新方法。为减小试验工作量,本文选取试验次数少、可靠性强的均匀设计法,采用其中的表U1*0(108),对包括支持电解质硫酸钾浓度、铁氰化钾浓度、多壁碳纳米管的浓度、铅笔芯的有效长度、扫描电位范围和富集时间等6个条件进行了6因素10水平优化试验。在最佳条件下,铁氰化钾的DPV还原峰电流下降值ΔI与氯吡脲浓度在0.75~1.75μmol/L范围成正比,检测限为4.20×10^(-2)μmol/L,氯吡脲体系可能共存的物质不干扰测定。采用本方法对施加过氯吡脲的猕猴桃果实进行测定,与标准方法LC-MS的检测结果一致。

Forchlorfenuron can inhibit the reduction reaction of potassium ferricyanide,and a new method for indirect determination of forchlorfenuron concentration by differential pulsed voltammetry(DPV)was established.In order to reduce the test workload,this paper selects a uniform design method with few test times and strong reliability,and uses the table to carry out 6 factors and 10 level optimization tests for six conditions,including the concentration of potassium sulfate supporting electrolyte,potassium ferricyanide concentration,concentration of multi-walled carbon nanotubes,effective length of pencil lead,scanning potential range and enrichment time.Under optimal conditions,the decrease in DPV reduction peak current of potassium ferricyanide is proportional to the concentration of chlorpyramide in the range of 0.75-1.75μmol/L,the detection limit is 4.20×10^(-2)μmol/L,and the substances that may coexist in the chloropyramide system do not interfere with the determination.The results of this method are in agreement with those of LC-MS.