Abstract

A highly sensitive enzyme-induced metallization-based electrochemical signal amplification strategy was developed based on the integration of the enzyme-induced metallization reaction, Au nanoparticles (AuNPs)-induced silver deposition, chemically modified electrode and highly sensitive stripping voltammetry detection. The presence of alkaline phosphatase (ALP) catalyzed ascorbic acid 2-phosphate into ascorbic acid, which reduced Ag⁺ to Ag⁰ on the surface of the AuNPs/multi-walled carbon nanotubes/polyethyleneimine/glassy carbon electrode (AuNPs/MWNTs/PEI/GCE). As a result, the enzyme-generated product was accumulated on the surface of the AuNPs/MWNTs/PEI/GCE by means of silver deposition via this signal amplification strategy, which enhanced the detection signal dramatically. Amounts as low as 1 × 10^–8 U/mL (corresponding to 10 aM) ALP can be detected using this strategy, which is about 4−7 orders of magnitude more sensitive than with other reported methods for ALP determination. In addition, this strategy can be applied to ALP detection in real complex samples, which shows great potential in the early diagnosis of diseases.

中文翻译：

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酶诱导的基于金属化的电化学信号放大策略，用于在高摩尔浓度下检测超高灵敏度碱性磷酸酶。

摘要

基于酶诱导的金属化反应，Au纳米粒子（AuNPs）诱导的银沉积，化学修饰的电极和高灵敏度的溶出伏安法检测的集成，开发了一种高灵敏度的基于酶诱导的金属化的电化学信号放大策略。碱性磷酸酶的存在（ALP）催化抗坏血酸2-磷酸转化成抗坏血酸，从而减少了的Ag ⁺到的Ag ⁰的纳米金/多壁碳的表面上的纳米管/聚乙烯亚胺/玻碳电极（金纳米粒子/碳纳米管/ PEI / GCE）。结果，通过这种信号放大策略，通过银沉积，酶产生的产物积累在AuNPs / MWNTs / PEI / GCE的表面上，从而大大增强了检测信号。使用这种策略可以检测到低至1×10 ^–8 U / mL（相当于10 aM）的ALP，其灵敏度比其他报告的ALP测定方法高约4-7个数量级。此外，该策略可应用于实际复杂样品中的ALP检测，在疾病的早期诊断中显示出巨大的潜力。