A visual detection assay for Helicobacter pylori in saliva based on recombinase-aided amplification and peptide nucleic acid-assisted split DNAzyme probes

Helicobacter pylori (H. pylori) infection can cause gastritis, gastric ulcer and even gastric cancer. It was therefore listed as a class Ⅰ carcinogen in 2007. H. pylori infection is also widespread in the world but is easy to be eradicated. Therefore, the timely diagnosis of H. pylori infection is significantly important. In this study, a visual detection assay for H. pylori in saliva based on recombinase-aided amplification (RAA) and peptide nucleic acid-assisted split DNAzyme probes was developed. The sampling was easy and the whole detection could be finished in 100 min with low dependence on incubation equipment. The detection results could be qualitatively identified by naked eyes and visual analysis based on ImageJ software, and quantitatively analyzed by spectrophotometry in the range of 0 – 10^5 CFU/mL H. pylori and the limit of detection is low to 0.105 CFU/mL. Thus, with the advantages of easy sampling, low equipment dependence and high sensitivity, the visual detection assay for H. pylori in saliva developed in this study could help control H. pylori infection.