Preparation of norovirus GII loop mediated isothermal amplification freeze-drying microsphere reagents and its application in an on-site integrated rapid detection platform

Norovirus is an infectious disease that can cause non-bacterial gastroenteritis, which has a low infectious dose, rapid onset, and strong transmission ability; therefore, rapid and sensitive detection is essential to reduce the transmission of gastroenteritis. In the study, a norovirus GII loop-mediated isothermal amplification assay was developed and prepared into freeze-drying microspheres, and a closed-cassette-based, integrated, reagent-ambient storage, on-site instant detection platform for norovirus GII was constructed using a commercial, fully automated nucleic acid analyzer with integrated magnetic bearing based nuclear acid extraction and nucleic acid detection, with a sensitivity of 10 copies/μL, with no cross-reactivity with other 5 viruses. For 28 simulated samples, the integrated assay platform was consistent with the experimental results of reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assays after conventional laboratory nucleic acid extraction. The entire process can be finished in about 1 h, which is ideal for immediate rapid detection.