Establishment of SARS-CoV-2 Quantification by Reverse Transcription Droplet Digital PCR
Keywords:
COVID-19, SARS-CoV-2, quantification, RT-ddPCRAbstract
Pandemic of SARS-CoV-2 affects global health, social, and economic system. Research and development in sciences and medicine involving diagnosis, therapy, and vaccine has been intensively focused to control this contagious virus. Quantification of SARS-CoV-2 viral load is important for studying pathology and monitoring treated patients, and also for standard RNA preparation. Quantitative real-time PCR technique has low accuracy, high variability, and required standard calibration in every run. Here, we reported the development of reverse-transcription droplet digital PCR (RT-ddPCR) method for SAR-CoV-2 detection which can absolutely quantitate the virus by detecting RNA dependent RNA polymerase (RdRp) gene as low as 800 copies/ml with linearity of detection at 1.8 x 103 to 5.54 x 106 copies/ml of RNA sample. This method can be applied to measure SARS-CoV-2 in both reference RNA and clinical samples. Further improvement in quality of biological samples in term of collection method and preservation will support the accuracy of the viral load assay.
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