Capillary Electrophoresis of PCR fragments with labelled primers for testing the SARS-Cov-2

GOMEZ, J.; MELON, S.; BOGA, J. A.; Alvarez-Arguelles, M. E.; ROJO-ALBA, S.; LEAL-NEGREDO, A.; Castello-Abietar, C.; ALVAREZ, V.; CUESTA-LLAVONA, E.; COTO, E.

doi:10.1101/2020.05.16.099242

bioRxiv · 10.1101/2020.05.16.099242

Capillary Electrophoresis of PCR fragments with labelled primers for testing the SARS-Cov-2

GOMEZ, J.·MELON, S.·BOGA, J. A.·Alvarez-Arguelles, M. E.·ROJO-ALBA, S.·LEAL-NEGREDO, A.·Castello-Abietar, C.·ALVAREZ, V.·CUESTA-LLAVONA, E.·COTO, E.

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Abstract

BackgroundDue to the huge demand for SARS-Cov-2 determination, alternatives to the standard qtPCR tests are potentially useful for increasing the number of samples screened. Our aim was to develop a direct fluorescent PCR capillary-electrophoresis detection of the viral genome. We validated this approach on several SARS-Cov-2 positive and negative samples. Study designWe isolated the naso-pharingeal RNA from 20 positive and 10 negative samples. The cDNA was synthesised and two fragments of the SARS-Cov-2 were amplified. One of the primers for each pair was 5-end fluorochrome labelled. The amplifications were subjected to capillary electrophoresis in ABI3130 sequencers to visualize the fluorescent peaks. ResultsThe two SARS-Cov-2 fragments were successfully amplified in the positive samples, while the negative samples did not render fluorescent peaks. ConclusionWe describe and alternative method to identify the SARS-Cov-2 genome that could be scaled to the analysis of approximately 100 samples in less than 5 hours. By combining a standard PCR with capillary electrophoresis our approach would overcome the limits imposed to many labs by the qtPCR (lack of reactive and real-time PCR equipment) and increase the testing capacity.

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GOMEZ, J., MELON, S., BOGA, J. A., Alvarez-Arguelles, M. E., ROJO-ALBA, S., LEAL-NEGREDO, A., Castello-Abietar, C., ALVAREZ, V., CUESTA-LLAVONA, E., COTO, E.. 2020-05-21. Capillary Electrophoresis of PCR fragments with labelled primers for testing the SARS-Cov-2. https://doi.org/10.1101/2020.05.16.099242

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