High-throughput extraction of SARS-CoV-2 RNA from nasopharyngeal swabs using solid-phase reverse immobilization beads

Mahesh K R Kalikiri; Mohammad Rubayet Hasan; Faheem Mirza; Thabisile Xaba; Patrick Tang; Stephan Lorenz

In this manuscript, we demonstrate the feasibility of using reagents commonly available in molecular biology and next-generation sequencing laboratories for the extraction of SARS-CoV-2 viral RNA for the diagnosis of COVID-19. This method has a comparable sensitivity and specificity with commercially available reference assays, especially when considering that the reference method uses 220 µl of sample, whereas this method only uses 150 µl. This method can be performed manually, with a throughput of maximum 48 samples in 90 minutes. In order to increase throughput and reproducibility and reduce human error, it can be implemented on many laboratory liquid-handling robots. In our hands, we were able to process 96 samples in 60 minutes. We made 2 methods for a Hamilton STAR liquidhandling system available on GitHub, processing either 24 or 96 samples per run. Future versions will make use of on-deck parallelization and offer a throughput of at least 192 samples in 60 min.