Transferable, easy-to-use and room-temperature-storable PCR mixes for microfluidic molecular diagnostics

Area of Science:

• Molecular Biology
• Biotechnology
• Diagnostic Technologies

Background:

• The COVID-19 pandemic highlighted the need for accessible on-site molecular diagnostics.
• Traditional Polymerase Chain Reaction (PCR) methods require careful reagent handling and specific storage conditions.

Purpose of the Study:

• To develop a freeze-drying method for PCR reagents suitable for microfluidic molecular diagnosis.
• To assess the stability and shelf-life of freeze-dried PCR reagents.
• To evaluate accelerated stability testing methods for predicting the shelf-life of freeze-dried PCR mixes.

Main Methods:

• Developed a freeze-drying technique to create stable, pre-mixed PCR reagent beads.
• Stored freeze-dried PCR mixes at room temperature (18-25°C) and accelerated conditions (56°C and 80°C) to assess stability.
• Investigated the applicability of the Q10 method for predicting shelf-life of freeze-dried PCR mixes.

Main Results:

• Freeze-dried PCR mixes demonstrated stability at room temperature for 1-2 years, with ongoing monitoring for longer periods.
• Accelerated stability testing at 56°C and 80°C reduced evaluation periods to less than one month.
• Findings challenged the Q10 method's universal applicability for freeze-dried PCR mixes, indicating influence from various factors.

Conclusions:

• Freeze-drying offers a viable method for creating stable, easy-to-use PCR reagents for microfluidic devices.
• This approach simplifies PCR operational steps, reduces errors, and enhances accessibility for molecular diagnostics.
• The study provides critical insights into the stability and shelf-life prediction of freeze-dried PCR reagents, benefiting both central labs and resource-limited settings.