Common laboratory organic solvents are better medium for molecular detection of RNA viruses using PCR

Indian J Med Microbiol. 2024 May 3:49:100596. doi: 10.1016/j.ijmmb.2024.100596. Online ahead of print.

Abstract

Purpose: The unavailability of recommended viral transport medium during epidemics of respiratory viral infections is a substantial healthcare concern. It may prompt the use of alternatives, which may give rise to results with questionable validity. The present study was carried out to assess and validate the utility of commonly available solvents in the hospital/healthcare set-ups which may be used as ready and economical alternatives to commercial VTMs.

Methods: To evaluate the readily available solvents as an alternative to VTM, cell culture supernatant of pH1N1 2009 isolate with HA titres of 1:4 and extracted viral RNA of SARS-CoV-2 were spiked in a 1:10 ratio in ethanol, acetone, methanol and were compared to commercially available VTM for detection of influenza virus by real time RT-PCR (qRT-PCR). The tubes were kept at room temperature 24 h, 48 h and 72 h. Ct values of the various solvents at different time points were compared and statistical analysis was performed using Python.

Results: The Ct values of the Influenza and SARS-CoV2 viral genes in each solvent were maintained for 3 days at room temperatures, suggesting viral samples were stably preserved in the solvent for 3 days.

Conclusion: Methanol was found to be the most promising solvent for increasing the stability of viral RNA thereby enhancing the molecular diagnosis of the concerned pathogen.

Keywords: Influenza virus (pH1N1); Molecular diagnosis; Organic solvents; Respiratory viruses; Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).