CRISPR/Cas9-based point-of-care lateral flow biosensor with improved performance for rapid and robust detection of Mycoplasma pneumonia

Abstract

Screening of acute respiratory infections causes serious challenges in urgent point-of-care scenarios where conventional methods are impractical and alternative techniques suffer from low accuracy, poor robustness, and reliance on sophisticated instruments. As an improvement to this paradigm, we report a point-of-care lateral flow biosensor (LFB) based on the recognition property of clustered regularly interspaced short palindromic repeats (CRISPR)/associated protein 9 (Cas9) and apply it to the detection of Mycoplasma pneumoniae (M. pneumoniae). The designed biosensor employs CRISPR/Cas9 for secondary recognition after preamplification of target gene using specific primer set, avoiding false positives caused by nontarget factors. The high amplification efficiency and low applicable temperatures of recombinase polymerase amplification brings the detection limit of the biosensor to 3 copies even at a preamplification temperature of 25 °C. Its practical application is further demonstrated with 100% accuracy by testing with 43 M. pneumoniae-infected specimens and 80 uninfected specimens. Additionally, the entire detection, including pretreatment, preamplification, CRISPR/Cas9 recognition, and visual analysis, can be completed in 30 min. Featured with the combination of CRISPR/Cas9 and LFB, the biosensor we developed herein ensures excellent convenience, accuracy, and robustness, which endows promising point-of-care screening potential for infectious pathogens.

Keywords: Acute respiratory infections; CRISPR/Cas9; Lateral flow biosensor; Mycoplasma pneumoniae; Pathogen; Point-of-care.