Development Of A Biomedical Sensor Based On Pump- Free Microfluidic Chip For Point Of Care Test

With the coming age of population aging in China,pay attention to public health status at early stage has become an irresistable trend.Prostate cancer(PCa)is the most frequent type of cancer for medium-elderly men around world,one of the key aspects to significantly reduce mortality risk is the early and accurate detection of PCa.However traditional laboratory medicine is expensive,sample and time consuming,it is not suitable for family health care or community hospital routine test.Thus in order to satisfy requirement of point-of-care test(POCT)for rapid detection at primary-level clinics and personal users,a novel amperometric electrochemistry sensor detection system was developed and combined with pump-free microfluidic chip used for prostate cancer markers detection.In this thesis the main research contents are as follow: 1.Design a pump-free microfluidic chip as a biosensor detection platform;a modification polydimethylsiloxane(PDMS)chip is used to enhance the capillary force in the channel and achieved pump-free fluid-driven;2.Design a portable three-electrode potentiostat system based on Arduino microcontroller;potential range is between-2.046 and 2.046 V.The output voltage resolution is 5mV,and the minimum current detection signal is 10nA;3.Design a application(APP)for Android smart phone based on appcan development platform;communication achieved between the potentiostat and the smart phone app by utilized Bluetooth module.The mobile phone APP function includes sending the command voltage,receiving detection current signal and displaying it.4.Pump-free microfluidic electrochemical for rapid PSA detection,The capture antibody was immobilized on the deposited gold electrode formed immunorecognition layer.According sandwich immunoassay,the PSA was detected by anti-PSA with horseradish peroxidase(HRP),HRP catalyzed the redox current signal generated by TMB.The whole process only need two sample loading step.PSA assays performed using amperometric biosensor result in the detection from 0 ng/mL to 200 ng/m L and LOD is 1 ng/m L.It is a simple portable electrochemistry detection system based on pump-free microfluidic chip and expect to combine with different electrochemical sensors for rapid intelligent POCT detection in the future.