Research On Key Technology Of Microfluidic Chip For Electrochemical Detection Of Glucose In Sweat

Non-invasive detection has attracted much attention because of its painless and convenient sampling process.At the same time,human sweat contains a variety of biochemical information related to individual health,so the detection of marker in sweat is of great significance.Existing studies have shown that the glucose level in sweat has a certain correlation with the glucose level in blood,so the blood glucose level of diabetic patients can be assessed by measuring the glucose concentration in sweat.Therefore,this study proposes a sweat glucose detection method based on microfluidic technology,designs and manufactures a microfluidic detection platform that can realize fluid self-driving to detect the glucose concentration in sweat.In this paper,a microfluidic chip was designed to realize fluid selfdriving.The polymer sheet was processed by carbon dioxide laser,and the influence of processing parameters on the fluid transport function of the chip was explored.At the same time,the detection electrode was processed by screen printing technology and the electrode was used to realize glucose detection.Finally,the microfluidic chip part was combined with the glucose detection part to complete the preparation of the microfluidic detection platform.The main content of this paper is as follows:(1)The carbon dioxide laser was used to process PMMA micro fluidic chip to explore the influence of design parameters and surface treatment process on the self-driving function of microfluidic chip.At the same time,the function of each capillary circuit element was characterized,and innovatively introduced the sponge structure of PDMS for the fluid crossscale transportation.Finally,the fluid self-driving was realized on the microfluidic chip;(2)In the light of the technological characteristics of the carbon dioxide laser processing polymer,the influence of the power of the laser,the speed of laser scans and the number of repeated scans on the function of the self-driving chip is explored.And test the self-driving function of the chip to ensure that the self-driving microfluidic chip can directly transport the sample to be tested to the detection part;(3)The screen printing technology was used to prepare electrodes for glucose detection,and this process included the design and processing of the screen,the preparation of electrodes,and the characterization of electrode performance.The reversibility,repeatability and consistency of the electrode were characterized by electrochemical methods to ensure that the prepared electrode can meet the requirements of subsequent glucose detection;(4)Glucose was catalyzed by glucose oxidase to achieve concentration detection.At the same time,the working parameters of the detection electrode were determined in this experiment.The working curve was fitted,and the specificity of the detection was verified.Finally,the glucose detection electrode was assembled with the microfluidic platform,and the standard concentration samples were tested and verified through the platform.It was found that applying the self-driving microfluidic chip to sweat glucose detection can greatly simplify the detection process and maintain its performance.