基于炭气凝胶修饰BDD电极的叔丁基对苯二酚的检测

摘要

利用炭气凝胶(CAs)修饰硼掺杂金刚石(BDD)电极对抗氧化剂叔丁基对苯二酚(TBHQ)进行检测.首先研究了裸BDD电极和CAs修饰BDD电极在5mM [Fe (CN)6]3-(含0.1M KCI)溶液中的循环伏安行为.与裸BDD电极相比,在CAs修饰BDD电极上,5mM [Fe (CN)6]3-的氧化峰电流提高了118.14％,△Ep降低了0.197V,说明CAs具有较高的电催化活性,可以促进电极表面的电子转移,加快反应速率.1 ×10-4M TBHQ在不同电极上的差分脉冲伏安结果表明,经CAs修饰后,氧化峰电流从0.53μA增加到11.79μA,峰电位从0.56V负移到0.273V.研究了不同缓冲液和修饰量对电极响应的影响,实验得出最佳缓冲液为0.1M高氯酸(含10％乙醇),最佳修饰量为10μL.在最优条件下,TBHQ的氧化峰电流与其浓度在5-150μM范围内呈线性关系,线性方程为Ip=0.1419c+3.1597 (R2=0.995),检出限为0.15μM.采用本方法测定实际样品大豆油中TBHQ的含量,回收率为98.05％-109.48％.%The Carbon Aerogel modified boron - doped diamond ( BDD) electrode has been successfully developed for the detection of Tertiary butylhydroquinone ( TBHQ) . Cyclic voltammetry was utilized to investigate the properties of the bare BDD electrode and the CAs - BDD electrode in a 0. 1M KC1 solution containing 5mM [Fe (CN)6]3-. Compared with bare BDD electrode,the oxidation peak current of 5mM [ Fe ( CN) 6]3- increased by 118. 14% on CAs — BDD e-lectrode,and the △Ep decreased by 0. 197V. This indicated that CAs had higher electrocatalytic activity and improved the electron transfer. The electrochemical behaviors of 1 10-4 M TBHQ on the bare and modified BDD electrode were studied. The results showed that the oxidation peak current increased from 0. 53 μA to 11. 79μA,and the oxidation peak potential negatively shifted from 0. 56V to 0. 273 V. The effect of different buffer solutions and modified quantity on the e-lectrode response showed that the optimal buffer solution was 0. 1 M HClO4 and the optimal modified quantity was l0μL. The current of TBHQ was proportional to its concentration in the range of 5 to 150μM,with a detection limit of 0. 15μM. The recoveries for Soybean oil samples obtained from the CAs - BDD sensor were calculated and the recovery was 98.05%~ 109.48%.