Magnetic Nanozyme-Enhanced Rapid ImmunoFlow-Through Assay for the Femtomolar Detection of Sugarcane Yellow Leaf Virus

Plant diseases significantly threaten global food security, with numerous historical instances of devastating epidemics. This risk is particularly acute in key agricultural and food crops, such as sugarcane. Although recent advancements in molecular diagnostics have improved the detection of sugarcane viruses, these methods are largely confined to lab settings due to their reliance on sophisticated, costly equipment. To overcome this limitation, we have developed a more accessible and cost-effective solution: a magnetic nanozyme-enhanced colorimetric ImmunoFlow-through assay designed for the ultrasensitive detection of sugarcane yellow leaf curl virus (ScYLV). This innovative technique allows for clear optical identification of viral concentrations as low as femtomolar levels. The assay employs cationic magnetic nanoparticles for virus isolation and colorimetric immunolabels for diagnosis, enhancing sensitivity and providing immediate results, comparable to those of established methods like quantitative real-time-polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA). Our assay offers a one-step detection process and a two-step semiquantitative analysis, marking a major breakthrough in plant virus diagnostics. Extensive research into the assay’s design, including its sensing platform, blocking agents, antibody conjugation chemistries, sensitivity, quantification, potential for multiplexing, and field applicability, was carried out. This diagnostic research utilizing Magnetozyme in a flow-through assay represents a pioneering approach to rapid and sensitive diagnosis within plant disease diagnostics. It introduces a promising alternative to traditional molecular diagnostics, potentially transforming plant disease management and enhancing food security globally.