TY - JOUR
T1 - A lyophilized colorimetric RT-LAMP test kit for rapid, low-cost, at-home molecular testing of SARS-CoV-2 and other pathogens
AU - Song, Xin
AU - Coulter, Felicity J.
AU - Yang, Ming
AU - Smith, Jessica
AU - Tafesse, Fikadu G.
AU - Messer, William
AU - Reif, John H.
N1 - Funding Information:
We are thankful to Prof. Rytas Vilgalys for offering us immediate training and access to the lyophilizer used in this study. We also thank Prof. Randy Smith, Dr. Peter Silinski, Dr. Liang Jiang, Prof. Katherine Franz, Prof. Paul Manos, Prof. Amanda Hargrove, Zhengguo Cai, Misty Roland, Samuel Kamau, and Melanie Eberhart for their assistance in coordinating facilities needed for this work during the campus lockdown. We also thank Prof. Xuan Qin in the OHSU Department of Pathology for providing CT values for our samples and the distribution of CT values for SARS-CoV-2 clinical tests performed at OHSU. We wish to thank all the frontline essential personnel for supporting our work during this challenging time. This work was supported by NSF grants CCF-1813805 and CCF-1909848 (J.H.R.).
Publisher Copyright:
© 2022, The Author(s).
PY - 2022/12
Y1 - 2022/12
N2 - Access to fast and reliable nucleic acid testing continues to play a key role in controlling the COVID-19 pandemic, especially in the context of increased vaccine break-through risks due to new variants. We report a rapid, low-cost (~ 2 USD), simple-to-use nucleic acid test kit for self-administered at-home testing without lab instrumentation. The entire sample-to-answer workflow takes < 60 min, including noninvasive sample collection, one-step RNA preparation, reverse-transcription loop-mediated isothermal amplification (RT-LAMP) in a thermos, and direct visual inspection of a colorimetric test result. To facilitate long-term storage without cold-chain, a fast one-pot lyophilization protocol was developed to preserve all required biochemical reagents of the colorimetric RT-LAMP test in a single microtube. Notably, the lyophilized RT-LAMP assay demonstrated reduced false positives as well as enhanced tolerance to a wider range of incubation temperatures compared to solution-based RT-LAMP reactions. We validated our RT-LAMP assay using simulated infected samples, and detected a panel of SARS-CoV-2 variants with successful detection of all variants that were available to us at the time. With a simple change of the primer set, our lyophilized RT-LAMP home test can be easily adapted as a low-cost surveillance platform for other pathogens and infectious diseases of global public health importance.
AB - Access to fast and reliable nucleic acid testing continues to play a key role in controlling the COVID-19 pandemic, especially in the context of increased vaccine break-through risks due to new variants. We report a rapid, low-cost (~ 2 USD), simple-to-use nucleic acid test kit for self-administered at-home testing without lab instrumentation. The entire sample-to-answer workflow takes < 60 min, including noninvasive sample collection, one-step RNA preparation, reverse-transcription loop-mediated isothermal amplification (RT-LAMP) in a thermos, and direct visual inspection of a colorimetric test result. To facilitate long-term storage without cold-chain, a fast one-pot lyophilization protocol was developed to preserve all required biochemical reagents of the colorimetric RT-LAMP test in a single microtube. Notably, the lyophilized RT-LAMP assay demonstrated reduced false positives as well as enhanced tolerance to a wider range of incubation temperatures compared to solution-based RT-LAMP reactions. We validated our RT-LAMP assay using simulated infected samples, and detected a panel of SARS-CoV-2 variants with successful detection of all variants that were available to us at the time. With a simple change of the primer set, our lyophilized RT-LAMP home test can be easily adapted as a low-cost surveillance platform for other pathogens and infectious diseases of global public health importance.
UR - http://www.scopus.com/inward/record.url?scp=85128995288&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85128995288&partnerID=8YFLogxK
U2 - 10.1038/s41598-022-11144-5
DO - 10.1038/s41598-022-11144-5
M3 - Article
C2 - 35487969
AN - SCOPUS:85128995288
VL - 12
JO - Scientific Reports
JF - Scientific Reports
SN - 2045-2322
IS - 1
M1 - 7043
ER -