School of Engineering, University of Guelph, Guelph, ON, N1G 2W1, Canada.
W. Booth School of Engineering Practice and Technology, McMaster University, Hamilton, ON, L8S 4L8, Canada.
Biosens Bioelectron. 2019 Jun 15;135:14-21. doi: 10.1016/j.bios.2019.03.056. Epub 2019 Apr 5.
Okadaic acid (OA) is one of the most prevalent and largely distributed bio-toxin in the world. Consumption of OA results in a series of digestive ailments such as nausea and diarrhea. This study demonstrates the preparation and functioning of an electrochemical microfluidic biochip for the detection of OA. The screen-printed carbon electrode (SPCE) was modified by phosphorene-gold nanocomposite onto which an aptamer specific to OA was immobilized. BP-Au nanocomposites were synthesized by an in-situ, one-step method without the use of a reducing agent. Potassium ferro-ferri cyanide was used as a redox pair to quantify signal strength. To improve reaction time, increase sensitivity and portability, a microfluidic platform was designed and developed. This device comprised of channels identified for specific purposes such as sample mixing and incubation. Overall, the integrated system consisted of a polydimethylsiloxane microfluidic chip housing an aptamer modified SPCE, as a single detection module for Okadaic acid. The nanomaterials and the microfluidic channels prepared were spectroscopically and electrochemically analyzed. Differential pulse voltammograms revealed a detection limit of 8 pM, while a linear range was found between 10 nM-250 nM. Selectivity studies were also performed with spiked mussel samples and other interfering species. This point-of-care device can be deployed to perform on-farm assays in fishing units.
冈田酸（OA）是世界上分布最广泛、最常见的生物毒素之一。食用 OA 会导致一系列消化疾病，如恶心和腹泻。本研究展示了一种用于检测 OA 的电化学微流控生物芯片的制备和功能。通过将磷烯-金纳米复合材料修饰在丝网印刷碳电极（SPCE）上，并将与 OA 特异性结合的适体固定化，来修饰 SPCE。BP-Au 纳米复合材料是通过原位一步法合成的，无需使用还原剂。铁氰化钾/亚铁氰化钾被用作氧化还原对来定量信号强度。为了提高反应时间、灵敏度和便携性，设计和开发了微流控平台。该装置由用于特定目的的通道组成，如样品混合和孵育。总的来说，集成系统由一个聚二甲基硅氧烷微流控芯片组成，其中包含一个经过适体修饰的 SPCE，作为 Okadaic 酸的单个检测模块。对纳米材料和微流道进行了光谱和电化学分析。差分脉冲伏安法显示检测限为 8 pM，而在 10 nM-250 nM 之间发现了线性范围。还对贻贝样品和其他干扰物质进行了选择性研究。这种即时检测设备可用于在渔业单位进行现场检测。
