Shen Yuchen, Shi YunYi, Wang Juan
School of Environmental and Chemical Engineering & Shanghai Key Laboratory of Materials Protection and Adv. Mater. in Electric Power, Shanghai University of Electric Power, Shanghai 200090, China.
Lab Chip. 2025 Jul 23;25(15):3730-3740. doi: 10.1039/d5lc00450k.
The escalating global concern over antibiotic contamination in food chains and aquatic ecosystems demands innovative solutions for rapid, on-site monitoring of residual drugs. This study presents an autonomous microfluidic photoelectrochemical (PEC) biosensing platform that synergizes magnetic purification, enzymatic amplification, and nanohybrid-enhanced signal transduction for field-deployable, ultrasensitive kanamycin (KAN) detection. The system integrates three functional layers: aptamer-functionalized magnetic beads (MBs) for selective KAN isolation, alkaline phosphatase (ALP)-catalyzed hydrolysis of L-ascorbic acid 2-phosphate (AAP) to generate electron-donating ascorbic acid (AA), and a TiO/NbC/carbon nitride (CN) photoanode with a type-II heterojunction architecture for an amplified photocurrent response. This cascaded mechanism achieves a 0.00142 nM detection limit (S/N = 3). Crucially, the polydimethylsiloxane (PDMS)-based microfluidic chip automates critical workflows-including target-probe mixing, dsDNA displacement, MB separation, and ALP-Apt transfer through serpentine channels and pressure-driven flow control, eliminating manual intervention. A wireless PEC module coupled with smartphone-based signal processing enables real-time parameter optimization and data transmission Bluetooth, removing reliance on external instrumentation. The modular design permits rapid adaptation to diverse targets through interchangeable aptamers, validated spike-recovery tests in real samples. By unifying enzymatic catalysis, magnetic microfluidics, and nanomaterial-engineered photoelectrochemistry, this work establishes a paradigm for decentralized biosensing that bridges laboratory-grade sensitivity with point-of-need practicality, addressing critical gaps in antibiotic monitoring for food safety and environmental surveillance.
全球对食物链和水生生态系统中抗生素污染的关注度不断升级，这就需要创新的解决方案来快速、现场监测残留药物。本研究提出了一种自主微流控光电化学（PEC）生物传感平台，该平台将磁净化、酶促放大和纳米杂化增强信号转导相结合，用于现场可部署的超灵敏卡那霉素（KAN）检测。该系统集成了三个功能层：用于选择性分离KAN的适配体功能化磁珠（MBs）、碱性磷酸酶（ALP）催化L-抗坏血酸2-磷酸酯（AAP）水解以生成供电子的抗坏血酸（AA），以及具有II型异质结结构的TiO/NbC/氮化碳（CN）光阳极，用于放大光电流响应。这种级联机制实现了0.00142 nM的检测限（S/N = 3）。至关重要的是，基于聚二甲基硅氧烷（PDMS）的微流控芯片实现了关键工作流程的自动化，包括靶标-探针混合、双链DNA置换、磁珠分离以及通过蛇形通道和压力驱动的流量控制进行ALP-适配体转移，消除了人工干预。一个无线PEC模块与基于智能手机的信号处理相结合，能够通过蓝牙实时优化参数并传输数据，不再依赖外部仪器。模块化设计允许通过可互换的适配体快速适应不同的靶标，并在实际样品中通过加标回收测试进行了验证。通过将酶催化、磁微流控和纳米材料工程化的光电化学相结合，这项工作建立了一种分散式生物传感的范例，将实验室级的灵敏度与现场实用性相结合，填补了食品安全和环境监测中抗生素监测的关键空白。
