Simulation of Microfluidics in a Meandering Channel and Viability of a Manufactured Microfluidic Device for Medical Applications

Abstract

A study was conducted on microfluidic mixers for the medical applications of screening alpha-1 antitrypsin deficiency and wound transport phenomena. A micromixer utilizes a microfluidic channel to mix feed streams, such as elastase and substrate or fibrinogen and thrombin. There are several micromixer designs, the simplest being a zig-zag channel. The research focuses on exploring how the design of microfluidic channel affects the mixing, using experimental and simulation approaches. A microfluidic mixer must be constructed to conduct microfluidics experiments, and a simulation is built using software as a precursory step to experimentation. The simulations were constructed and calculated using ComSol® . After building the initial mixer channel, the particular physics and conditions were applied in order to produce a concentration profile. The steps to manufacture a micromixer include: designing the zig-zag template, preparing a PDMS gel, submerging the template in PDMS, curing PDMS, dissolving the template, then running microfluidic experiments. Inconsistencies were found in the produced PDMS gels for each trial. Some gels were solid and firm, while others remained viscous. Also, the ABS templates were not easily dissolved with acetone. The simulations yielded results about the relationship between geometry, diffusion coefficient, degree of mixing, and residence time. To further the research, the procedure must be refined to produce gels that are consistent for each trial. Some recommendations include: finding the ideal ratio of elastomer to curing agent, finding the ideal oven temperature and heating time, finalizing a micromixer geometry, and finding the solubility of ABS in concentrated acetone.