Helicosign Dry is an in vitro diagnostic kit for detection of H.pylori (H. pylori) infection by qualitatively measuring the presence of urease secreted by H. pylori using gastric mucosal tissue. The reagent contains urea, that is a substrate of urease secreted by H. pylori, and pH indicator. When urea is degraded by urease, ammonium ion is generated and pH is changed. At this time, the pH indicator changes from yellow to purple, and the result is decided.