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Sensitive extraction-free SARS-CoV-2 RNA virus detection using a chelating resin.

ABSTRACT: Current conventional detection of SARS-CoV-2 involves collection of a patient's sample with a nasopharyngeal swab, storage of the swab during transport in a viral transport medium, extraction of RNA, and quantitative reverse transcription PCR (RT-qPCR). We developed a simplified preparation method using a chelating resin, Chelex, which obviates RNA extraction during viral testing. Direct detection RT-qPCR and digital droplet PCR were compared to the current conventional method with RNA extraction for simulated samples and patient specimens. The heat treatment in the presence of Chelex markedly improved detection sensitivity as compared to heat alone, and lack of RNA extraction shortens the overall diagnostic workflow. Furthermore, the initial sample heating step inactivates SARS-CoV-2 infectivity, thus improving workflow safety. This fast RNA preparation and detection method is versatile for a variety of samples, safe for testing personnel, and suitable for standard clinical collection and testing on high-throughput platforms.

SUBMITTER: Guan B

PROVIDER: S-EPMC8349732 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Sensitive extraction-free SARS-CoV-2 RNA virus detection using a novel RNA preparation method.

Project description:Current conventional detection of SARS-CoV-2 involves collection of a patient sample with a nasopharyngeal swab, storage of the swab during transport in a viral transport medium, extraction of RNA, and quantitative reverse transcription PCR (RT-qPCR). We developed a simplified and novel preparation method using a Chelex resin that obviates RNA extraction during viral testing. Direct detection RT-qPCR and digital-droplet PCR was compared to the current conventional method with RNA extraction for simulated samples and patient specimens. The heat-treatment in the presence of Chelex markedly improved detection sensitivity as compared to heat alone, and lack of RNA extraction shortens the overall diagnostic workflow. Furthermore, the initial sample heating step inactivates SARS-CoV-2 infectivity, thus improving workflow safety. This fast RNA preparation and detection method is versatile for a variety of samples, safe for testing personnel, and suitable for standard clinical collection and testing on high throughput platforms.

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Fast, cheap and sensitive: Homogenizer-based RNA extraction free method for SARS-CoV-2 detection by RT-qPCR.

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| S-EPMC10035754 | biostudies-literature

A Saliva-Based RNA Extraction-Free Workflow Integrated With Cas13a for SARS-CoV-2 Detection.

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