A rapid and on-site visual sensor for tobacco mosaic virus detection based on photocatalytic molecularly imprinted ZnO nanorods

A photocatalytic molecularly imprinted sensor based on zinc oxide nanorods (ZnO NRs) for the visual detection of tobacco mosaic virus (TMV)TVM is reported. The sensor operates through virus-selective binding within molecularly imprinted cavities, which suppresses the photocatalytic degradation of Brilliant Green (BG) under visible light, enabling semi-quantitative visual readout within 5 min. The ZnO NRs serve a dual role as the photoactive transducer and structural scaffold, facilitating selective TMV recognition without requiring any biological reagents (e.g., antibodies or enzymes) or RNA extraction, aligning with the principles of reagent minimization and waste prevention in Green Analytical Chemistry (GAC). The entire analytical process is designed to be environmentally benign. For on-site application, a rapid screening protocol enables visual readout within 5 min without any instrumentation. This system achieves a detection limit of 0.96 pM, with recoveries of 93.7-106.4%. With a cost of only RBM 0.07 per test, the rapid visual protocol offers a scalable, farmer-friendly solution for rapid field detection of TMV, exemplifying a sustainable and green analytical workflow for enhancing crop protection and sustainable agriculture.