Maximising the Use of Scarce qPCR Master Mixes.

Area of Science:

• Molecular diagnostics
• Biochemistry

Background:

• The COVID-19 pandemic caused a surge in demand for molecular diagnostic testing, particularly real-time quantitative PCR (qPCR).
• This led to global shortages of testing capacity, equipment, and reagents, with extended supply times and increased costs for essential master mixes.
• Academic laboratories face significant challenges in maintaining qPCR assay capabilities due to reagent scarcity and high prices.

Purpose of the Study:

• To validate cost-effective strategies for optimizing reagent usage in qPCR assays.
• To address reagent shortages and high costs impacting academic research and diagnostics.
• To demonstrate the feasibility of using expired reagents and reduced master mix concentrations without compromising assay performance.

Main Methods:

• Validation of "past expiry date" master mixes against newly purchased ones for both standard and fast qPCR protocols.
• Assessment of qPCR efficiency and sensitivity using master mixes at less than 1x final concentration.
• Comparative analysis of assay performance under different reagent conditions.

Main Results:

• "Past expiry date" master mixes demonstrated equivalent performance to newly purchased ones in qPCR assays.
• Reduced master mix concentrations (less than 1x) did not compromise qPCR efficiency or sensitivity.
• Both strategies proved effective in stretching reagent supplies while maintaining assay integrity.

Conclusions:

• The use of "past expiry date" master mixes is a viable strategy for maintaining qPCR performance.
• Diluting master mixes to less than 1x concentration is a practical method to conserve reagents without sacrificing assay quality.
• These validated approaches offer significant benefits for academic laboratories facing reagent scarcity and budget constraints, enhancing molecular diagnostic capabilities.