Chemistry Department, Faculty of Applied Science, Umm Al-Qura University, Makkah, Saudi Arabia.
Department of Chemistry, Faculty of Science, Assiut University, Assiut, Egypt.
PLoS One. 2019 Jan 16;14(1):e0210652. doi: 10.1371/journal.pone.0210652. eCollection 2019.
Aflatoxins (AFs) are a family of fungal toxins that produced in food and feed by two Aspergillus species (Aspergillus flavus and Aspergillus parasiticus). Several techniques have been reported for AFs detection including high-pressure liquid chromatography, enzyme-linked immunosorbent assay, surface plasmon resonance and recombinant immune blotting assay. But, these methods are disadvantaged because they consumed a long time for analysis; in addition, they required a piece of complicated and expensive equipment. Therefore, developing of inexpensive sensors with high selectivity and sensitivity for detecting of AFs levels without extensive sample preparation has received great attention. Several electrochemical AFs sensors have been reported; however, there is still a need for developing a new, simple and rapid electrochemical AFs sensor. Here, we have developed a new AFs sensor based on Au nanostructures/graphene nanosheets modified ITO substrate that could enhance the Raman effect and the electrochemical conductivity. The modified electrode was prepared based on layer-by-layer electrochemical deposition method. AFs antibody was immobilized onto the Au nanostructures/graphene nanosheets; then it was used as a probe for rapid, simple and cheap detection of AFs level using Raman spectroscopy and electrochemical techniques. Our results demonstrated that the developed system showed a simple, easy and sensitive sensor for monitoring low concentrations of AFB1 with a detection limit of about 6.9 pg/mL, also it allowed the determination of AFB1 in spiked food samples.
黄曲霉毒素（AFs）是由两种曲霉（黄曲霉和寄生曲霉）在食品和饲料中产生的真菌毒素家族。已经报道了几种用于检测 AFs 的技术，包括高压液相色谱法、酶联免疫吸附测定法、表面等离子体共振和重组免疫印迹测定法。但是，这些方法存在分析时间长、需要复杂昂贵的设备等缺点。因此，开发具有高选择性和灵敏度、无需广泛样品制备的廉价传感器来检测 AFs 水平受到了极大关注。已经报道了几种电化学 AFs 传感器；然而，仍然需要开发一种新的、简单和快速的电化学 AFs 传感器。在这里，我们开发了一种基于 Au 纳米结构/石墨烯纳米片修饰 ITO 基底的新型 AFs 传感器，该传感器可以增强拉曼效应和电化学导电性。修饰电极是基于层层电化学沉积法制备的。AFs 抗体固定在 Au 纳米结构/石墨烯纳米片上；然后，它被用作探针，用于使用拉曼光谱和电化学技术快速、简单和廉价地检测 AFs 水平。我们的结果表明，该开发系统显示出一种简单、易用和灵敏的传感器，用于监测低浓度的 AFB1，检测限约为 6.9 pg/mL，还可以用于测定添加到食品样品中的 AFB1。
