Research On Design And Manufacture Of Microfluidic Concentration Gradient Chip Based On Rapid Customization

Micro fluidic technology is an attractive technology for the construction of biological systems in vitro.It provides a convenient platform for the study of cell co-culture,cell metabolic activity,cell-cell interaction and drug metabolism mechanism.With the further application of micro fluidic chips in the laboratory,the demand for the number and function of microfluidic chips in the laboratory is also increasing.Traditional chip manufacturing concepts and fabrication processes can not meet the needs of the laboratory for fast acquisition of functional chips.The exploration of rapid customization of microfluidic chip functions has become an important issue in chip manufacturing.In this paper,a rapid customization method of microfluidic concentration gradient chip is proposed based on light-cured 3D printing technology(SLA).Based on the general concentration gradient generation algorithm,a dendritic structure concentration gradient module with different functions is designed,and a modular combination of concentration gradient chip is obtained by combining the dendritic structure concentration gradient module with different cell culture modules.In order to verify the feasibility of the rapid customization scheme,the combination scheme of linear concentration gradient module and rectangular culture chamber module is selected as the validation scheme for the follow-up study.Firstly,based on the general concentration gradient distribution algorithm,the positions of diversion nodes in the tree network structure are calculated and designed,and the minimum length of the serpentine mixing channel is calculated based on the theory of liquid laminar diffusion in the microchannel.Finally,the overall structure of the channel is determined.After completing the design of the relevant parameters of the concentration chip,this paper uses Solidworks software to build the three-dimensional model of the designed chip module,and uses Fluent fluid simulation software to simulate and analyze the generation of the concentration gradient of the structure.Finally,the error between the simulation results and the design values is less than 5%,which preliminarily verifies the structure design.Reliability.After completing all the design work,this paper uses desktop-level UV-curable 3D printing equipment to fabricate the above chips quickly,and discusses the optimization process of printing parameters in detail.To solve the problem of chip bonding,a reversible bonding scheme of "PMMA-chip module-PDMS-chip module-PMMA" structure is proposed,and the bonding mode is optimized to improve the bonding effect of the chip.Finally,the reliability of the bonding scheme is verified by leak detection experiments.After the fabrication of the chip,the methyl violet solution was used to test the actual concentration gradient generation of the chip.The concentration gradient distribution generated by the chip was numerically detected by means of image average gray level characterization.The test results conformed to the theoretical design values and verified the concentration gradient chip.Functional reliability.Finally,HUVEC cells were implanted into the microarray and cultured on the cell wall.Through microscopic observation,it was found that the cells grew well in the culture chamber,indicating that the concentration gradient microarray customized in this paper had good biocompatibility.Based on the above experimental results,the feasibility of the rapid customization scheme of the concentration gradient chip proposed in this paper is finally verified.