Validation of a Lysis Buffer Containing 4 M Guanidinium Thiocyanate (GITC)/ Triton X-100 for Extraction of SARS-CoV-2 RNA for COVID-19 Testing: Comparison of Formulated Lysis Buffers Containing 4 to 6 M GITC, Roche External Lysis Buffer and Qiagen RTL Lysis Buffer

Martina F Scallan; Catherine Dempsey; John MacSharry; Isabelle O'Callaghan; Paula M O'Connor; Conor P Hogan; Edel Durack; Paul D. Cotter; Sarah Hudson; Humphrey A Moynihan; Brigid Lucey

The key chemical constituent of the lysis buffer (guanidinium thiocyanate) has become scarce, scientists from the School of Microbiology, University College Cork, combined their long-held knowledge of lysis buffers for RNA extraction, with insights from published work relating to extraction of RNA using magnetic glass beads (Chomczynski & Sacchi, 1987; Hui He et al., 2017) . Ultimately, they formulated a lysis buffer, which uses much less guanidinium thiocyanate than standard formulations appear to use (4 M compared to 6 M). Simultaneously, scientists at Teagasc, Fermoy were working on a different experimental formulation for lysis buffer (Boom et al., 1990) . Four laboratory preparations in total were tested for efficacy by medical scientists based in the Clinical Microbiology Department at Cork University Hospital (CUH), who conducted validation experiments using positive and negative samples. After validation, pharma-based scientists, generously prepared a large volume of the much needed 4 M GITC lysis buffer for distribution by CUH.