Optical Imaging Paper-based Microfluidic Sensors And Applications

Fluid detection technology has become an important way of human health testing.With the rapid development of microelectronics technology and biotechnology,bioanalysis system has developed in the direction of minitype,convenience,high detection throughput,easy operations and low cost.Paper-based microfluidics technology was born at the right moment based on paper-based platform.This is a kind of solidifying hydrophobic substance in the hydrophilic paper-base,forming the liquid shunting control technology.Paper-based microfluidics biosensor has the advantages of minitype,high detection throughput,convenience and real-time detection.Therefore,it is widely used in the environmental monitoring and detection in food safety and human healthIn this thesis,a method of controlling the fluid velocity is put forward to be proposed to solve the phenomenon of material aggregation in the paper-based microfluidics technology(phenomenon of “coffee ring”).Study the micro-escalation droplets' law of motion in the rectangular paper carrier through theoretical modeling and extract the control methods of liquid flow rate.The main achievements are as follows:(1)The writer has studied the motion mechanism of droplets in the rectangular paper carrier.Through the modeling analysis,the writer found there was congruent relationship between the wetting velocity of droplets in the rectangular paper carrier and the length of rectangular paper-base,which could be used to control the fluid velocity.(2)The saturation coefficient was proved by modeling analysis that it had no influence on the velocity,which would no longer be considered in the subsequent modeling analysis.From the modeling analysis in the reaction zone,the writer found that the best pattern in the triangular reaction zone was equilateral triangular.(3)Based on the theoretical modeling analysis,a kind of low-speed paper-based carrier was developed to improve the phenomenon of material aggregation in biological detection analysis.The glucose colorimetric analysis proved that this paper-based carrier had the function of material distribution control,which made the material evenly distributed in the reaction zone.(4)A kind of glucose sensor was developed with the use of low-speed paper-based carrier and the function relationship between the glucose concentration and the figure signal strength was also established.Combining with the camera phone,a kind of data collection system of human health information was constituted to achieve the remote disease detection analysis and data collection of human health for the public.It was certainly meaningful for the development of medical apparatus and instruments in the family practice or occasions of bedside detection analysis.In addition,for the feature of weak gray-scale identification signal,the arithmetic was used to enhance the colorimetric signal and improve the detecting limitation of low-speed glucose sensor,so that it could be suitable for the wider use of the public.