Multiplexed and Extraction-Free Amplification for Simplified SARS-CoV-2 RT-PCR Tests

Area of Science:

• Molecular Biology
• Virology
• Clinical Diagnostics

Background:

• The COVID-19 pandemic highlighted challenges in accurate disease diagnosis due to supply shortages and complex testing procedures.
• Current RNA extraction and RT-PCR methods are costly, time-consuming, and require specialized expertise, limiting widespread testing capacity.

Purpose of the Study:

• To develop and validate an extraction-free, multiplexed amplification assay for SARS-CoV-2 RNA detection.
• To assess the performance of this assay across various clinical samples and reagent combinations.

Main Methods:

• An extraction-free, multiplexed RT-PCR assay was developed using CDC singleplex targets.
• The assay was tested on 246 clinical samples, evaluating different master mixes and transport media.
• Limit of Detection (LoD) was determined to be 2 copies/μL.

Main Results:

• The developed assay demonstrated 86% sensitivity and 100% specificity for SARS-CoV-2 RNA detection.
• Successful amplification was achieved using various master mixes and transport media, indicating assay robustness.
• The assay's LoD was found to be 2 copies/μL.

Conclusions:

• The extraction-free, multiplexed RT-PCR method offers a simplified, cost-effective, and rapid approach for COVID-19 diagnostics.
• This method can enhance testing capacity and provide accurate results even with fluctuating supply availability.
• The findings provide guidance for reagent selection to ensure reliable diagnostic outcomes during the pandemic.