Design And Research Of Portable POCT Helicobacter Pylori Detecto

Helicobacter pylori(H.pylori)is a common pathogenic bacterium which can be transmitted among people through feces,drinking water,food,oral cavity and other channels.Studies have shown that the infection rate of H.pylori in China is as high as 50%,and H.pylori infection may lead to gastric ulcer,gastric cancer and other serious consequences.Therefore,early detection,early diagnosis and early treatment can effectively avoid the serious consequences of H.pylori.However,the H.pylori test method currently used in clinics needs expensive instruments,complex operation,long detection time and professional technicians,which is difficult to be used for daily universal screening.It is urgent to develop a rapid,simple and sensitive H.pylori detection strategy and equipment for rapid and accurate screening of H.pylori.To solve this problem,a portable H.pylori detector based on Point-of-Care Testing technology is designed and developed by using electrochemical biosensor.The portable H.pylori detector is mainly composed of handheld electrochemical instrument,smart phone app and electrochemical detection chip.For the detection of very low content of H.pylori,the designed handheld electrochemical instrument needs to have the characteristics of miniaturization and high sensitivity.Therefore,this paper designs and builds an electrochemical system with time current curve as the quantitative method,including voltage scanning module,constant potential module,current measurement module,data acquisition module,microcontroller module,communication module and power supply module.In order to realize fast data reading and result presentation,an app based on smart phone system is designed.Finally,based on screen printed electrode,a sandwich electrochemical biosensor with aptamer and monoclonal antibody as double probes and horseradish peroxidase as electrochemical signal marker was constructed to detect H.pylori with high sensitivity and specificity.During the construction of the electrochemical biosensor,the assembly process of the interface was characterized by cyclic voltammetry,and the sensing interface was optimized.Using the optimal experimental conditions,different concentrations of H.pylori were detected.The results showed that when the concentration was between 1～10~5 CFU/m L,the current signal was linear with the logarithm of H.pylori concentration.Because the portable H.pylori detector has the advantages of rapidity,simplicity,high sensitivity and specificity,it is expected to use for the rapid screening of clinical H.pylori to reduce the incidence of gastric diseases and gastric cancer.