Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China.
Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture, Wuhan 430062, China.
Toxins (Basel). 2020 Mar 3;12(3):158. doi: 10.3390/toxins12030158.
Sensitive and point-of-care detection of small toxic molecules plays a key role in food safety. Aflatoxin, a typical small toxic molecule, can cause serious healthcare and economic issues, thereby promoting the development of sensitive and point-of-care detection. Although ELISA is one of the official detection methods, it cannot fill the gap between sensitivity and point-of-care application because it requires a large-scale microplate reader. To employ portable readers in food safety, Pt-catalysis has attracted increasing attention due to its portability and reliability. In this study, we developed a sensitive point-of-care aflatoxin detection (POCAD) method via a portable handheld barometer. We synthesized and characterized Au@PtNPs and Au@PtNPs conjugated with a second antibody (Au@PtNPs-IgG). A competitive immunoassay was established based on the homemade monoclonal antibody against aflatoxins. Au@PtNPs-IgG was used to catalyze the production of O from HO in a sealed vessel. The pressure of O was then recorded by a handheld barometer. The aflatoxin concentration was inversely proportional to the pressure recorded via the barometer reading. After optimization, a limit of detection of 0.03 ng/mL and a linear range from 0.09 to 16.0 ng/mL were achieved. Recovery was recorded as 83.1%-112.0% along with satisfactory results regarding inner- and inter-assay precision (relative standard deviation, RSD < 6.4%). Little cross-reaction was observed. Additionally, the POCAD was validated by high-performance liquid chromatography (HPLC) by using peanut and corn samples. The portable POCAD exhibits strong potential for applications in the on-site detection of small toxic molecules to ensure food safety.
灵敏且即时检测小分子毒物在食品安全中起着关键作用。黄曲霉毒素是一种典型的小分子毒物，它会引发严重的健康和经济问题，从而推动了灵敏且即时检测技术的发展。尽管酶联免疫吸附测定（ELISA）是一种官方检测方法，但由于需要大型微孔板读取器，因此无法满足灵敏度和即时检测应用的要求。为了在食品安全中使用便携式读取器，Pt 催化因其便携性和可靠性而受到越来越多的关注。在这项研究中，我们通过便携式手持气压计开发了一种灵敏的即时检测黄曲霉毒素（POCAD）的方法。我们合成并表征了 Au@PtNPs 和与第二抗体（Au@PtNPs-IgG）偶联的 Au@PtNPs。基于针对黄曲霉毒素的自制单克隆抗体建立了竞争性免疫测定法。Au@PtNPs-IgG 用于在密封容器中催化 HO 产生 O。然后，通过手持气压计记录 O 的压力。黄曲霉毒素的浓度与通过气压计读数记录的压力成反比。经过优化，检测限为 0.03 ng/mL，线性范围为 0.09-16.0 ng/mL。回收率为 83.1%-112.0%，内和间试验精密度（相对标准偏差，RSD<6.4%）均令人满意。交叉反应性很小。此外，使用花生和玉米样品通过高效液相色谱（HPLC）验证了即时检测的准确性。这种便携式即时检测方法具有在现场检测小分子毒物以确保食品安全方面的巨大应用潜力。
