POL Scientific / JBM / Volume 11 / Issue 2 / DOI: 10.14440/jbm.2024.0001
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Impact of relative humidity on SARS-CoV-2 RNA extraction using Nextractor automated extraction system

Rajeev Kumar Jain1 Archa Sharma2 Jaya Lalwani2 Deepti Chaurasia2 Nagaraj Perumal1*
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1 State Virology Laboratory, Department of Microbiology, Gandhi Medical College, Bhopal, Madhya Pradesh, 462001, India
2 Department of Microbiology, Gandhi Medical College, Bhopal, Madhya Pradesh, 462001, India
JBM 2024 , 11(2), e99010012; https://doi.org/10.14440/jbm.2024.0001
Submitted: 16 March 2024 | Revised: 30 May 2024 | Accepted: 5 June 2024 | Published: 4 July 2024
© 2024 by the Journal of Biological Methods published by POL Scientific. Licensee POL Scientific, USA. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )

This study investigated the influence of relative humidity (RH) on the efficiency of SARS-CoV-2 RNA extraction using the Nextractor automated system. Experiments employing clinical samples demonstrated satisfactory sensitivity and reproducibility for RNA extraction at low humidity (below 50% RH). Conversely, extractions at high humidity (above 70% RH) resulted in complete failure of reverse transcription-polymerase chain reaction assays, with neither SARS-CoV-2 RNA nor the human RNase P gene (internal control) detected. Analysis suggested that residual ethanol, incompletely evaporating due to high humidity, acted as a potent polymerase chain reaction inhibitor in these samples. These findings highlighted the importance of maintaining optimal laboratory humidity (<50% RH) for reliable SARS-CoV-2 RNA extraction using the Nextractor system. Furthermore, laboratories should implement strategies such as regular humidity monitoring, staff training on humidity’s impact, and system validation under specific humidity conditions to ensure accurate molecular diagnostic workflows for COVID-19 testing.

RNA Extraction
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Conflict of interest
The authors declare no conflict of interest.
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Journal of Biological Methods, Electronic ISSN: 2326-9901 Print ISSN: TAB, Published by POL Scientific