Molecular Dx Significance 7/10

One-Pot CRISPR/Cas12a Assay With Ultrashort HDA Detects Respiratory Pathogens at Attomolar Levels

A novel isothermal amplification method (ultrashort HDA) paired with CRISPR/Cas12a enables one-pot nucleic acid detection at 37 degrees in under one hour, with a limit of detection of 5 aM. Tested on 58 clinical specimens for influenza A and 24 for Staphylococcus infection, the assay achieved 100% sensitivity and specificity versus PCR. The extraction-free, low-complexity format has strong point-of-care potential.

The original study

One-Pot CRISPR/Cas12a Assay Based on Ultrashort HDA for Ultrasensitive and Universal Nucleic Acid Detection.

Authors
Liao H, Xie H, Ye H, Liu X, Chen Y, Zhong R, et al.
Journal
Analytical chemistry
PMID
41871234
Read the original study →

Original abstract

Isothermal amplification techniques, such as helicase-dependent amplification (HDA) combined with CRISPR, are cutting-edge approaches for nucleic acid detection. In this work, we developed a novel ultrashort mesophilic HDA (termed usHDA) for rapid, highly sensitive nucleic acid amplification at 37 °C and constructed a one-pot usHDA-CRISPR/Cas12 assay. The usHDA is specifically designed for rapid amplification of ultrashort sequences (about 40 nt) at 37 °C within 30 min. This usHDA-CRISPR/Cas12a detection can be completed within 1 h, achieving a limit of detection (LOD) of 5 aM. When tested on 58 clinical specimens from patients infected with respiratory pathogens, this assay identified 41 positive and 17 negative samples for influenza A virus. This assay achieved 100% sensitivity, 100% specificity, and a perfect receiver operating characteristic curve (area under the curve value = 1.00; n = 58) compared with PCR analysis. Furthermore, 24 samples of Staphylococcus infection were detected using usHDA-CRISPR/Cas12a, and the same 100% sensitivity and specificity were achieved. These findings highlighted the strong applicability of our proposed assay for universal nucleic acid detection.