Specificity investigation, (a) Gray values of the specificity testing results using a smartphone camera by simultaneously identifying B. pertussis from B. parapertussis and B. holmesii. (b) Gel electrophoresis analysis. Lane 1: 100 bp marker; Lanes 2-3: LAMP products from B. pertussis and B. parapertussis DNA samples; Lanes 4-5: LAMP products from B. pertussis and B. holmesii DNA samples. All LAMP zones were preloaded with B. pertussis LAMP primers. Different DNA samples of B. pertussis, B. parapertussis, and B. holmesii (5 × 106 copies per LAMP zone), as well as the NC2 (without template DNA), were individually introduced into their corresponding LAMP zones.