Reusable Visualization Photoelectrochromic Molecularly Imprinting Chip Lower-Voltage Driven by Photoassisted Fuel Cells

Visual sensors are extensively utilized in the domain of point-of-care testing (POCT), because of their key benefit of providing results that are simple to interpret. Electrochromic materials, as an essential component of visual sensors, have a large driving voltage, which is an important limiting factor affecting the detection performance of such sensors. In this study, a reusable, portable, and self-powered visual sensor was developed, integrating a photoassisted fuel cell (PFC) as a portable power source (signal generation region, SG region) and an ultralow voltage driven photochromic/electrochromic visualization part (signal output region, SO region) as a color display component. The SO region can achieve an ultralow voltage (0.1 V) electrochromic effect with the help of external ultraviolet light and has reversible color change performance. At the same time, the use of a molecular imprinting polymer (MIP) shortens the detection time of the sensor, reduces the experimental cost, and shows excellent detection performance. To demonstrate its practical applicability, the sensor was applied to the visual detection of ochratoxin A (OTA), achieving a broad linear response range from 0.1 to 110 ng/mL, with an impressive detection limit as low as 0.06 ng/mL. This PFC-driven visual sensor offers a low-cost, portable, and instrument-free solution for on-site mycotoxin detection, highlighting its strong potential for applications in food safety monitoring and environmental screening.