Swellable Microneedle-coupled Light-addressable Photoelectrochemical Sensor for In-situ Tracking of Multiple Pesticides Pollution In Vivo

In vivo monitoring of multiple pesticide contamination is of great significance for evaluating the health risks of different pesticides, agricultural production safety, and ecological and environmental assessment. Here, we report a hydrogel microneedle array coupled light-addressable photoelectrochemical sensor for tracking multiple pesticide uptake and elimination in living animals and plants, holding three prominent merits: i) enables in-situ detection of in vivo pesticides, avoiding cumbersome and complex sample transportation and handling processes; ii) allows repeated in vivo sampling of the same organism, improving tracking test controllability and accuracy; iii) avoids lethal sampling, providing a better understanding of the pesticides fate in living organisms. The coupled sensor is mechanically robust for withstanding more than 0.35 N per needle and highly swellable (800%) for timely extraction of sufficient in vivo solution for analysis. For proof-of-concept, it achieves in-situ detection of atrazine, acetamiprid, and carbendazim efficiently and quantitatively in artificial agarose skin models, mouse skin interstitial fluids, and plant leaves with little inflammatory reaction. This simple, highly integrated, minimally invasive, and high-throughput in vivo monitoring method is ideal for future field environmental monitoring and plant and animal disease diagnosis. Most of the used pesticide contaminants can be enriched in plants and animals through various pathways and eventually enter the human body to cause various chronic or acute diseases. Therefore, the development of sensing technologies capable of in-situ tracking of the uptake and elimination of pesticides in vivo is essential to fully assess their environmental and ecological risks. Herein we demonstrate a hydrogel microneedle array coupled-photoelectrochemical sensor for light-addressable and direct in-situ monitoring of multiple pesticides in living animals and plants, which not only avoids complex environmental sample preprocessing processes but also provides timely feedback on environmental quality issues.