A simple magnetic nanoparticles-based viral RNA extraction method for efficient detection of SARS-CoV-2

Zhen Zhao; Haodong Cui; Wenxing Song; Xiaoling Ru; Wenhua Zhou; Xuefeng Yu

Herein, a further simplified and updated MNPs-based viral RNA extraction method is described for highly sensitive extraction and RT-PCR detection of viral RNA using SARS-CoV-2 pseudoviruses as models. The MNPs is synthesized via a simple one-pot approach, and functionalized with polymers carrying multi-carboxyl groups by following one-step incubation. Due to the strong interaction between carboxyl groups and nucleic acids, the poly carboxyl-functionalized MNPs (pcMNPs) enables rapid and efficient absorption of RNA molecules. In RNA extraction, one lysis/binding step and one washing step are required for nucleic acids extraction and purification from complex samples. More importantly, extracted RNA can be directed introduced into subsequent RT-PCR together with MB without elution step, which dramatically reduce operating time and risk of contamination. The fast extraction method was verified by both manual operation and automated system. Due to its simplicity, satisfactory performances and robustness, this method provides a promising alternative to decrease the labour-intensity and reduce possibility of false-negative results in current RT-PCRbased SARS-CoV-2 diagnosis.