Optimal Stabilization for Long-Term Storage of Nucleic Acid-Based CRISPR/Cas12a Assay for SARS-CoV-2 Detection

Abstract

In this long-term storage study, we optimized the lyophilization conditions of each reaction stage of a nucleic acid-based assay for SARS-CoV-2 detection. The stability testing demonstrated that the dried reactions from all 3 steps (cDNA synthesis, isothermal amplification and detection) can be kept at ¡20 °C or 4 °C for up to 6 or 3 months, respectively, whereas, if stored at 25 °C or 37 °C, the reagents only could be stored for a few days without quality loss. This suggests that we can have the dried reactions at ¡20 °C for long-term storage until needed. Moreover, this assay is now simpler to perform as each of the 3 steps now proceeds with pre-mixed regents lyophilized in a single tube for each step.