Multi-Channel Electrochemical Test Strip For Smartphone-Based Multiplex Biosensing

With the significance of health problems and the shortage of existing medical resource,the study on point-of-care testing(POCT)has become popular.Electrochemistry,an ancient subject,and smartphone,an epoch-making equipment both supplement each other,which provides a new conception for POCT:electrochemical methods makes quantitative detection become rapid,sensitive and convenient while smartphones can offer an integrated systematic platform.The research on multiple test strip based on electrochemical methods and smartphone platform will assist people in examining body conditions with less cost and operations.Herein,two forms of test strip and two forms of auxiliary detection equipment were designed.One form of the multiple test strips finish detections of glucose,lactic acid and uric acid in body fluid by oxidase membrane electrode method and open circuit voltage method.And the other finish detections of potassium ion,sodion and calcium ion with help of ion selective electrode method and solid quasi-reference electrode.Both test strips have three layers and the top and the bottom are made of PET film while the middle layer is made of hydrophobic double-sided adhesive.One strip is consisted of three channels,three corresponding carbon working electrodes and a shared silver reference electrode,which meet the requirement of detecting three analytes at same time.The two forms of auxiliary detection equipment both collect multi-voltage from electrode by analog-digital conversion,and communicate with a smartphone by universal serial bus(USB)or Bluetooth respectively.Then with assistant of application installed,the results are calculated and shown on the screen.To summarize,the test strips and the auxiliary detection equipment plus a smartphone form a simple POCT system,which is cheap,portable and easily-operated,making routine body detections rather convenient for users.