Advancing Microfluidic Photoelectrochemical Aptasensing Platform with Photogenerated Carrier Regulation for Protein Biosynthesis Inhibitors Detection

Regulating the microscale carrier transport in semiconductor materials to enhance the macroscopic photoelectrochemical properties would drive technological advancement and industrial upgrading. In this work, we integrated the maturity of microfluidic technology control methods with current photoelectrochemical analysis sensing techniques to establish a microfluidic photoelectrochemical induction system by modulating the photon-to-current efficiency under zero bias. Traditionally, target recognition has been achieved by affecting the transport of carriers through the space resistance equivalent of the solid-liquid contact interface, which is limited in sensitivity enhancement. In this work, we presented an in situ ion exchange reaction that directly affects SnO₂/CdLa₂S₄ semiconductor structure and bandgap matching to achieve accurate detection of the protein biosynthesis inhibitor kanamycin. We developed a microfluidic system to precisely control the flow of the analyte solution, ensuring the controlled delivery of copper ions in proportion to the kanamycin concentration by a hybridization chain reaction within the recognition area. The integration of the microfluidic photoelectrochemical aptasensing platform enhanced the performance of the platform in terms of sensitivity and limits of detection. This work could open up new possibilities for the development of highly efficient and reliable aptasensing systems for various applications in the biomedical and environmental fields.