Chemical Detection by Analyte-Induced Change in Electrophoretic Deposition of Gold Nanoparticles
Chemical Detection by Analyte-Induced Change in Electrophoretic Deposition of Gold Nanoparticles
复制标题
通过分析物诱导的金纳米粒子电泳沉积变化进行化学检测
DOI：
10.1149/1945-7111/ac418c
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发表时间：
2022
影响因子：
3.9
通讯作者：
Zamborini, Francis P
中科院分区：
文献类型：
--
作者：
Mainali, Badri P;Zamborini, Francis P
柠檬酸盐稳定的Au纳米粒子（cit-Au NPs）在氧化铟锡（ITO）涂层的玻璃电极上发生电泳沉积（EPD），电化学氧化对苯二酚（HQ）时由于水合氢离子的释放。Au氧化的阳极溶出伏安法（ASV）允许在特定的EPD电位和时间下测定Au NP沉积的量。Cr 3+与cit-Au纳米粒子的结合通过诱导聚集和/或减少负电荷来抑制EPD，这可能降低cit-Au纳米粒子的有效NP浓度和/或降低电泳迁移率。这降低了ASV中的Au氧化电荷，其作为Cr 3+的间接信号。三聚氰胺与cit-Au NP的结合类似地导致聚集和/或降低负电荷，也导致ASV Au氧化峰的降低。ASV法测得的Au氧化电荷的减少量随Cr 3+和三聚氰胺浓度的增加而线性增加。对于直径为15.1和4.1 nm的cit-Au纳米粒，Cr 3+的检测限（LOD）分别为21.1 ppb和16.0 ppb。改善传感条件允许低至1 ppb的Cr 3+检测。对于4.1 nm Au NP，三聚氰胺的LOD为45.7 ppb。
The electrophoretic deposition (EPD) of citrate-stabilized Au nanoparticles (cit-Au NPs) occurs on indium tin oxide (ITO)-coated glass electrodes upon electrochemical oxidation of hydroquinone (HQ) due to the release of hydronium ions. Anodic stripping voltammetry (ASV) for Au oxidation allows the determination of the amount of Au NP deposition under a specific EPD potential and time. The binding of Cr 3+ to the cit-Au NPs inhibits the EPD by inducing aggregation and/or reducing the negative charge, which could lower the effective NP concentration of the cit-Au NPs and/or lower the electrophoretic mobility. This lowers the Au oxidation charge in the ASV, which acts as an indirect signal for Cr 3+. The binding of melamine to cit-Au NPs similarly leads to aggregation and/or lowers the negative charge, also resulting in reduction of the ASV Au oxidation peak. The decrease in Au oxidation charge measured by ASV increases linearly with increasing Cr 3+ and melamine concentration. The limit of detection (LOD) for Cr 3+ is 21.1 ppb and 16.0 ppb for 15.1 and 4.1 nm diameter cit-Au NPs, respectively. Improving the sensing conditions allows for as low as 1 ppb detection of Cr 3+. The LOD for melamine is 45.7 ppb for 4.1 nm Au NPs.