Research On New Technology Of Microfluidic Chip-Mold Cloning And 3D Printing

Microfluidic chip technology has received extensive attention due to its characteristics of miniaturization,high throughput and low consumption.Through scientific research and technological innovation,microfluidic chip technology has achieved quite good technical landing results in the fields of environmental monitoring,biomedicine and medical health.Especially in the medical and health field,with the aggravation of social aging and the continuous enhancement of people’s health awareness,people have generated a lot of demand for obtaining various parameters of the body through in vitro diagnosis.And microfluidic technology has a place in the field of in vitro diagnostics because of its many excellent characteristics.In this paper,by investigating the development status of microfluidic chips,the current microfluidic chip fabrication methods,chip materials and consistency control are reviewed.A clearer understanding of microfluidic chip fabrication methods and material selection for different applications.Then,in view of the requirement of using q PCR method to simultaneously detect multiple mutations of Mycoplasma pneumoniae,3D printing technology was selected as the method to fabricate microfluidic chips.The effects of different chip materials and coatings on PCR reactions were tested to help select more economical chip materials.The combination of the various parts of the 3D printed chip and the construction of the microvalve were achieved by a simple adhesive tape method.Then it is verified whether the bonding strength of the chip assembled by this method and the closing performance of the microvalve meet the requirements.Finally,the microfluidic chip was successfully used to detect clinical samples of Mycoplasma pneumoniae.Aiming at the problem of large differences between different batches of microfluidic chips in the manufacture of microfluidic chips by soft lithography,a new mold cloning method was proposed.This method utilizes the characteristic of sustainable suction after degassing of PDMS,which can make the prepolymer fill the microchannel of the PDMS stamp,and finally solidify the prepolymer to realize the cloning of the mold.In this paper,photoresist was chosen as the material for mold cloning.For the problem of high viscosity of commonly used photoresist,a method of diluting the photoresist is proposed.By testing the volatilization rate of different dilution solvents,γ-butyrolactone was selected as the dilution solvent of photoresist.Faced with the problem of photoresist deformation caused by the accumulation of solvent volatilized gas in the closed state,a method of reducing the external air pressure was proposed.Finally,using the improved mold cloning process,the same original master mold was cloned with different dilution ratios of photoresist,and the effects of dilution ratio and original master mold size on the replication accuracy were analyzed.This research topic discusses how to select the fabrication methods and materials of microfluidic chips to achieve the goal under the existing requirements.And how to use mold cloning technology to improve consistency when the consistency of microfluidic chips is strictly required.Therefore,this study provides a certain reference for the design,manufacture and consistency improvement of microfluidic chips.