Catalytic amplification by transition-state molecular switches for direct and sensitive detection of SARS-CoV-2

Sci Adv. 2021 Mar 17;7(12):eabe5940. doi: 10.1126/sciadv.abe5940. Print 2021 Mar.

Abstract

Despite the importance of nucleic acid testing in managing the COVID-19 pandemic, current detection approaches remain limited due to their high complexity and extensive processing. Here, we describe a molecular nanotechnology that enables direct and sensitive detection of viral RNA targets in native clinical samples. The technology, termed catalytic amplification by transition-state molecular switch (CATCH), leverages DNA-enzyme hybrid complexes to form a molecular switch. By ratiometric tuning of its constituents, the multicomponent molecular switch is prepared in a hyperresponsive state-the transition state-that can be readily activated upon the binding of sparse RNA targets to turn on substantial enzymatic activity. CATCH thus achieves superior performance (~8 RNA copies/μl), direct fluorescence detection that bypasses all steps of PCR (<1 hour at room temperature), and versatile implementation (high-throughput 96-well format and portable microfluidic assay). When applied for clinical COVID-19 diagnostics, CATCH demonstrated direct and accurate detection in minimally processed patient swab samples.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • COVID-19 Nucleic Acid Testing* / instrumentation
  • COVID-19 Nucleic Acid Testing* / methods
  • COVID-19* / diagnosis
  • COVID-19* / genetics
  • Humans
  • Lab-On-A-Chip Devices*
  • Limit of Detection
  • Microfluidic Analytical Techniques*
  • Point-of-Care Testing*
  • SARS-CoV-2 / genetics*