State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, PR China.
State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, PR China; Jiangxi-OAI Joint Research Institute, Nanchang University, Nanchang 330047, PR China.
Talanta. 2018 Aug 15;186:29-35. doi: 10.1016/j.talanta.2018.04.018. Epub 2018 Apr 8.
Naked-eye readout colorimetric signal-based assays are promising for high-throughput screening detection and point-of-care diagnostics in resource-constrained regions. Here, a novel direct competitive plasmonic enzyme-linked immunosorbent assay (dc-pELISA) based on gold nanoparticle (AuNP) aggregation with highly sensitive and robust naked-eye readout signal was developed and used to detect fumonisin B (FB). AuNP aggregation was induced by a horseradish peroxidase (HRP)/hydrogen peroxide (HO)/tyramine (TYR) system, resulting in a dramatic color change from red to blue. In this system, HO was produced via GOx-mediated glucose oxidation reaction, and FB-GOx was used as a competitive antigen. The proposed pELISA demonstrated good linear detection of FB from 3.125 ng mL to 25 ng mL with a vivid color change from deep blue to red and a cutoff limit of 12.5 ng mL observed by the naked eye. The average recoveries for FB-spiked corn samples ranged from 76.5% to 96.8% with a relative standard derivation of 4.88~ 16.4%. Meanwhile, the proposed method exhibited excellent agreement (R = 0.927) with the conventional ELISA method in blindly detecting FB spiked corn samples. Additionally, the results of the proposed method for FB positive corn samples also showed a high consistency with those of the ultra performance liquid chromatography method. These results indicated acceptable accuracy and precision of the proposed colorimetric ELISA for quantitative detection of FB in actual corn samples.
基于裸眼比色信号的比色分析方法在资源有限地区的高通量筛选检测和即时诊断方面具有广阔的应用前景。在这里，我们开发了一种基于金纳米粒子（AuNP）聚集的新型直接竞争等离子体酶联免疫吸附测定法（dc-pELISA），并用于检测伏马菌素 B（FB）。AuNP 聚集是由辣根过氧化物酶（HRP）/过氧化氢（HO）/酪胺（TYR）系统诱导的，导致颜色从红色急剧变为蓝色。在该体系中，HO 是通过 GOx 介导的葡萄糖氧化反应产生的，FB-GOx 被用作竞争抗原。所提出的 pELISA 表现出良好的线性检测 FB 的能力，从 3.125ng/mL 到 25ng/mL，具有生动的颜色变化，从深蓝色变为红色，并且可以通过肉眼观察到 12.5ng/mL 的截止值。用玉米样品对 FB 进行加标回收实验，平均回收率在 76.5%到 96.8%之间，相对标准偏差为 4.88%到 16.4%。同时，该方法与传统 ELISA 方法在盲法检测 FB 加标玉米样品时具有良好的一致性（R = 0.927）。此外，该方法对 FB 阳性玉米样品的检测结果与超高效液相色谱法也具有高度一致性。这些结果表明，所提出的比色 ELISA 方法用于定量检测实际玉米样品中的 FB 具有良好的准确性和精密度。
