【摘要】 水滑石类化合物是一种层状双羟基复合金属化合物(LDH),有良好的电吸附和电催化性能。研究利用共沉淀方法合成Ni/Mg/Fe三元水滑石材料,并将其掺入碳糊中制成碳糊电极,用于检测食品中的亚硝酸盐。结果表明,合成的三元水滑石对亚硝酸根离子具有明显的吸附与催化氧化效果,提高了碳糊电极的电化学检测性能;在亚硝酸盐浓度为5～700μmol/L范围内均具有良好的线性关系(相关系数大于0.998),最小检测限为0.49μmol/L。对扫描电位、扫描速率、静置时间、pH值、修饰剂量等条件进行优化,进一步提高了检测灵敏度。将此方法用于实际食品样品检测,平均加标回收率为(100±10)%,表现出良好的检测效果。与现有方法相比,该方法测定亚硝酸盐具有稳定性和重现性良好、灵敏度高、响应快速、线性范围宽、干扰小、仪器设备简单等优点。更多还原

【Abstract】 Hydrotalcite-like compounds are layered double hydroxide composite metal compounds(LDHs),which show good electrical adsorption and electrocatalytic properties.In this study Ni/Mg/Fe ternary LDH was synthesized by coprecipitation and mixed with carbon paste to prepare carbon paste electrodes for detection of nitrite in food.The results showed that the synthesized LDH had obvious adsorption and catalytic oxidation effects on nitrite iron and the electrochemical performance of the chemically modified carbon paste electrode was greatly improved.There was a good linear relationship(correlation coefficient was higher than 0.998) over the concentration range of 5-700 μmol/L and the minimum detection limit was 0.49 μmol/L.The conditions of scanning potential,scanning speed,accumulation time,pH and the amount of modifier were also optimized to further improve the detection sensitivity.The method was further applied to analyze food samples,and the average recovery rates were(100 ± 10)%,which showed good detection peformance.Compared with other detection methods,this method showed the advantages of high stability,reproducibility and sensitivity,rapid response,wide liner range,little interference and simple instruments.The new electrode can be used in pratice with good application prospects.更多还原