Micro-fluidic diffusion coefficient measurement

摘要

A new method for diffusion coefficient measurement applicable to micro-fludics is presented. The method utilizes an analytical model describing laminar dispersion in rectangular micro-channels. The method was verified through measurement of fluorescein diffusivity in water and aqueous polymer solutions of differing concentration .The diffusivity of fluorescein was measured as 0.64x10~-9m~2/s in the 4 gm/dl dextran solution and 0.38x10~-9m~2/s in the 8 gm/dl dextran solution.