纳米金/离子液体修饰碳糊电极同时检测对苯二酚和邻苯二酚

Simultaneous determination of hydroquinone and catechol using carbon paste electrode modified by gold nanoparticle and ionic liuquid

制备了纳米金/离子液体修饰碳糊电极,用循环伏安法研究了对苯二酚和邻苯二酚在该修饰电极上的电化学行为,同时研究了支持电解质、缓冲溶液、pH及扫描速率对邻苯二酚和对苯二酚循环伏安响应的影响。研究表明:在pH 8. 8的磷酸盐缓冲溶液中,扫速为100 mV/s时,对苯二酚和邻苯二酚在纳米金/离子液体修饰碳糊电极上响应电流较强,氧化峰电位差为164. 0 mV,还原峰电位差为116. 1 mV,故修饰碳糊电极对邻苯二酚和对苯二酚均有催化活性且可同时检测。对苯二酚的线性范围为0. 600~200μmol/L,相关系数r=0. 999,检出限为0. 077μmol/L;邻苯二酚的线性范围为0. 140~200μmol/L,相关系数r=0. 999,检出限为0. 010μmol/L。将该方法用于水体分析,回收率为95. 6%~104. 4%。

Carbon paste electrode( CPE) inonic liquid was prepared. Electrochemical behavior of hydroquinone( HQ) and catechol( CC) the electrode was investigated by cyclic voltammetry. Effects of electrolyte,buffer solution,pH value and scanning rate were inverstigated. In a phosphate buffer solution with p H 8. 8,hydroquinone and catechol showed strong response at this gold/ionic liquid modified electrode at the scan rate of100 m V/s. Two peaks difference for oxidation or reduction were 164. 0 m V or 116. 1 m V,respectively. The modified carbon paste electrodes can catalytze the HQ and CC,and the two substances could be detected without separation simultaneously. Furthermore,the proposed sensor showed a rapid and highly sensitive linear response to HQ in the range of 0. 600-200 μmol/L with a detection limit of 0. 077 μmol/L( r = 0. 999). In addition,it showed a rapid and highly sensitive linear response to CC in the range of 0. 140-200 μmol/L with a detection limit of 0. 010 μmol/L( r = 0. 999) The methods was used to water analysis with the recovery of95. 6%-104. 4%.