Improving the Mixing Performance of a 3D Lab-on-a-chip Device by using Fluid Dynamics Simulation

抄録

In the present paper, the mixing performance of a 3D lab-on-a-chip device, which is used for small immunoassay systems for medical diagnosis and environmental analysis such as enzyme-linked immunosorbent assay (ELISA), was investigated by using 3D fluid dynamics simulation and design of experiment (DOE) to optimize the micro channel structure. The degree of mixing was calculated by a three-dimensional finite element analysis code “Fluent” applying k-ε model, which is a typical turbulence model, changing design parameters (temperature, angle, flow rate, viscosity, length, hole diameter, degree of overlap). 18 sets of conditions determined by DOE were conducted. As a result, it was found that the effective parameters for promoting the mixing were half-cross structure, smaller tilt angle and higher viscosity, probably due to enhancement of shear stress in the fluid. Furthermore, in the newly suggested structures “half-cross” and “improved halfcross”, the degrees of mixing were improved to 40% and 60% respectively, in comparison to the conventional mixing structures of “straight” and “full cross” which showed the degrees of mixing of 10% and 25% respectively.