Vacuum Oven Drying: A Cost-Effective Way of Producing Field-Deployable Reagents for In-house Real-Time PCR Methods

Mol Biotechnol. 2025 Jan;67(1):237-245. doi: 10.1007/s12033-023-00999-2. Epub 2023 Dec 22.

Abstract

The polymerase chain reaction (PCR), is a widely used, sensitive and reliable method for detecting pathogens. However, technical limitations may restrict its use outside sophisticated laboratories, e.g. for detecting pathogens at the site of a disease outbreak. In this study, real-time PCR reagents specific to four bacteria (Bacillus anthracis, Yersinia pestis, Francisella tularensis, and Brucella spp.) and to the Influenza A virus were dried using a vacuum oven drying method. The performance of the dried reagents stored at different temperatures, was monitored using both a standard-size and a portable real-time PCR instrument. The vacuum oven dried real-time PCR reagents were stable and retained the sensitivity for at least 14 months when stored in a refrigerator (+ 4 °C). When stored at room temperature, DNA assays remained stable for at least 10 weeks and Influenza A RNA assay for 3 weeks. These results demonstrate the feasibility of vacuum oven dried real-time PCR reagents and a portable thermocycler for the rapid and reliable detection of pathogens. The drying protocol presented here is cost-effective and easy to use, and could be applied to real-time PCR methods specific to other pathogens as well. In addition, this in-house drying protocol reduces reliance on commercial PCR tests during a time of shortage, such as that experienced during the Corovirus disease (COVID-19) crisis.

Keywords: Biothreat countermeasures; Field detection; Polymerase chain reaction; Portable PCR instrument; Vacuum oven dried PCR reagents.

MeSH terms

  • Cost-Benefit Analysis
  • Desiccation / methods
  • Francisella tularensis / genetics
  • Francisella tularensis / isolation & purification
  • Humans
  • Indicators and Reagents / chemistry
  • Influenza A virus / genetics
  • Influenza A virus / isolation & purification
  • Real-Time Polymerase Chain Reaction* / economics
  • Real-Time Polymerase Chain Reaction* / instrumentation
  • Real-Time Polymerase Chain Reaction* / methods
  • Vacuum
  • Yersinia pestis / genetics
  • Yersinia pestis / isolation & purification

Substances

  • Indicators and Reagents