Numerical Simulation And Fabrication Of Concentration Gradient Generator

The environment that simulates the concentration gradient in organisms has been shown to play a role in a wide range of biological processes.biomolecular gradients are an important signaling mechanism to guide cell growth,migration,and differentiation in living tissues.To elucidate these phenomena requires the ability to expose cells to quantifiable,controllable,and simulated biomolecular gradients.The rapidly developing microfluidic technology has become a new platform for the development of new concentration gradient generators.This paper is based on controlled diffusive mixing of species in solutions that are flowing laminarly,at low Reynolds number,inside a network of microchannels.A variety of new concentration gradient generators are designed,which can produce precise,controllable,stable and quantitative concentration gradients.Firstly,this paper introduces the research status and background of concentration gradient generator at home and abroad,and explains the significance of this paper.Then according to the production mechanism of the concentration gradient generator,a basic Christmas tree type concentration gradient generator is designed,and the influence of different inlet quantity and different inlet velocity on the production concentration gradient is compared.Furthermore,a Christmas tree-type concentration gradient generator based on cantor fractal structure was designed.The influence of fractal series,microchannel height and different inlet velocity on the concentration gradient was analyzed by numerical simulation.Lastly,the processing of the concentration gradient generator is studied.In this paper,the different concentration gradient generator is designed by using the CO₂ laser machine for PMMA,PS,PET three kinds of chips.A Christmas tree-type concentration gradient generator was fabricated with a PMMA chip.The effects of different laser processing parameters on microchannels were investigated by orthogonal experiment.A disk-type concentration gradient generator was fabricated with a chip of PS material,and the influence of laser processing parameters on microchannel roughness was also investigated by orthogonal test.A step-by-step concentration gradient generator was fabricated with a pet chip,and the influence of different laser power and speed on the depth and width of microchannels was investigated.Through the simulation and experimental study of the concentration gradient generator,the structure of various concentration gradient generators is designed in this paper.And the cantor fractal is introduced into the design of microchannel of the concentration gradient generator,which can obtain different concentration gradient curves.It has certain guiding value for the future study of concentration gradient generator.