Study On Chemiluminescence Immunoassay Based On Centrifugal Microfluidic Chip

All kinds of infectious diseases have always been one of the major threats to global public health.For example,COVID-19 caused by novel coronavirus has had a very negative impact on life and health,public health,social stability and economic development all over the world from 2019 to now.As a rapid,direct,and highly sensitive method for detecting infectious diseases,various detection methods based on immunological principles are also developing towards efficiency,automation,and high sensitivity.As one of the typical representatives of the current next-generation immune detection technology,chemiluminescence immunoassay(CLIA)is widely used in various detection fields such as tumors,infectious diseases,metabolic diseases,and pregnancy detection.Currently,chemiluminescence detection is often completed by large automated testing instruments equipped in large hospital inspection centers,which have high requirements for the testing environment and operator quality,making it difficult to promote and apply it to various grassroots medical institutions,including grassroots hospitals.With the integration of various functional modules on lab on a chip(LOC)and the automated fluid drive provided by microfluidic networks,microfluidic technology has gradually been applied in several in vitro diagnostic fields such as nucleic acid detection and immune analysis.Centrifugal microfluidic chips,as a typical representative of microfluidic chips,use the centrifugal force provided by the high-speed centrifugal motion of the chip to drive reagents to complete each step of reaction in sequence,simplifying fluid driving and reducing system complexity.They have unique advantages in high-throughput,automation,parallel detection,and other aspects.The main research content of this article is a chemiluminescence detection system based on centrifugal microfluidic chips,including centrifugal microfluidic chips and portable detection devices.The two work together and can automatically complete chemiluminescence detection.It has the characteristics of simple operation,small volume,low cost,and high flexibility,which is conducive to achieving Point of Care Testing(POCT)chemiluminescence detection.This article is based on centrifugal microfluidic technology and studies a microfluidic system for chemiluminescence detection,including centrifugal microfluidic chips and portable detection devices.A centrifugal chemiluminescence detection microfluidic chip based on magnetic bead method was studied and constructed,which utilizes centrifugal force to drive various reagent fluids to gradually complete various reactions,significantly simplifying the complexity of the chip.Especially,with the help of centrifugal force driving,several functions such as the fixation and transfer of magnetic beads within the chip,the mixing of magnetic beads and reagents,the quantitative directional driving of reagents,and the discharge of waste liquid under different states are achieved by combining the centrifugal chip with external magnet motion control.By constructing multiple detection units(channels)on centrifugal chips and utilizing a unified centrifugal force driving platform,parallel detection of multiple samples is easily achieved.We have developed a portable detection device for microfluidic systems,implemented centrifugal chip drive control based on servo motors,and collected and analyzed chemiluminescence signals using magnetic beads.The portable detection device includes several functional modules,including centrifugal drive module,magnet control module,incubation chamber module,chemiluminescence signal detection module,temperature control module,automatic liquid transfer module,etc.We have researched and implemented an embedded software and hardware system for a portable detection device.At the same time,we have designed and implemented a software for upper computer control and signal analysis.Based on the principle of magnetic bead chemiluminescence reaction and the timing control of each reaction step,we have achieved the operation control of the detection device and the collection and analysis of chemiluminescence signals through the mutual cooperation between various units in the system.By cooperating with microfluidic chips and detection devices,automated detection of chemiluminescence reactions in multi-channel mode based on magnetic bead method has been achieved,and its technical feasibility has been verified.