基于对铂纳米粒子过氧化物模拟酶活性的抑制检测碘离子

摘要

合成了柠檬酸钠保护的铂纳米粒子(PtNPs),其具有类过氧化物酶活性,可催化四甲基联苯胺(TMB)和过氧化氢的反应,产生有色产物;而碘离子(I-)对铂纳米粒子的催化活性具有明显的抑制作用,一定范围内随着I-浓度的增加,抑制作用逐渐增强,基于此构建了一种简单、快速测定I-的比色传感方法.I-的肉眼识别可在几秒内完成,定量检测可在10 min之内完成.此方法灵敏度高,检出限为8 nmol/L,检测范围较宽,为20~5000 nmol/L.相对于以纳米粒子的聚沉-分散为基础的比色法,此方法不需要纳米粒子的表面修饰,没有复杂的有机合成过程,操作简便、成本低.将此方法成功用于实际食盐样品和水样中I-的检测,效果良好.%As an important inorganic element, iodine not only plays an important role in human growth and metabolism, but also has an irreplaceable role in the chemical engineering, medicine, food and other fields.Thus the detection of iodine ion is of important significance.In this work, colorimetric recognition and sensing of iodine ion with high sensitivity was proposed based on target induced shielding of the peroxidase-like activity of bare platinum nanoparticles ( PtNPs ).This assay exhibited simplicity and cost-effectiveness.The recognition of iodine ion by bare PtNPs could be fulfilled in a few seconds and the assay could be accomplished within 10 min.The detection range for iodine ion was 20 nmol/L-5.0 μmol/L and the detection limit was 8 nmol/L ( S/N = 3 ).Furthermore, the new assay system did not require surface modification of nanoparticles, nor complex organic synthesis.This assay was successfully applied to detection of iodine concentration in real salt and water samples, exhibiting promising application prospects.