A highly uniform lamination micromixer with wedge shaped inlet channels for time resolved infrared spectroscopy

Abstract

We present a horizontal multi-lamination micromixer with specially wedge shaped vertical fluid inlets for fast and highly uniform fluid mixing in the low millisecond range. The four-layer laminar flow is created by a fluidic distribution network, reducing the amount of fluid connectors to the macroscopic world to two. All the geometries of the channel inlets and the distribution network were optimized for low flow rates and hence for low sample consumption using CFD simulations. The device materials applied feature low absorption in the mid-infrared (wavelength 3-10 lm) allowing to use this device for time resolved infrared spectroscopy. The micromixer itself can be built by silicon micromachining techniques without the need of complicated fabrication steps. Due to a transparent calcium fluoride cover optical measurements are possible as well which were used to characterize the device. Mixing times in the range of 1 ms with optical color measurements of aqueous solutions and with time resolved infrared measurement of the proton exchange reaction of H 2 O and D 2 O are achieved.

In-plane microvortices micromixer-based AC electrothermal for testing drug induced death of tumor cells

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Microfluidic hydrodynamic focusing for synthesis of nanomaterials

“…Given the latter, the average mixing time τ mix can be calculated using the following equation: $${\tau }_{\mathrm{italicmix}}\propto x^2/D$$ where x is the diffusion length (the distance that the solute needs to travel during the diffusion), and D is the diffusion coefficient. In low Re microfluidic systems, various mixing mechanisms have been demonstrated [17] using active approaches, such as magnetic [18,19], electrokinetic [20], acoustic [21–23], optical based [24] as well as passive approaches such as tesla microstructures [25,26], serpentine channels [27], and lamination [28]. These approaches either require an external mechanism to induce mixing or lacks the dynamic control of the fluid interface.…”

Applications of Microfluidics in the Agro-Food Sector: A Review

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