A micro-device for the mixing of a highly viscous bio-sample with water using micro-channel

A mechanism for controlling the mixing of highly viscous bio-samples at the micro-liter scale is presented. Existing methods for mixing bio-samples using micro-stirrers or shaking micro-wells are only effective for non-highly-viscous materials. The proposed mechanism mixes monoolein, a highly viscous bio-sample, with water in a micro-device called micro-capsule using a micro-channel and centrifugation. To achieve effective mixing, the design of the micro-capsule along with the micro-channel is presented and so is the hydrodynamic model describing the flow of viscous materials in the micro-channel. The mixing process is analyzed according to the Reynolds number of the bio-samples, which is observed during the experiment using digital images for further analysis. Finally, the new approach is verified by X-ray diffraction experiments, which are used to evaluate the effectiveness of mixing. Experimental results not only validate the proposed method but also determine the flow oscillation time in the micro-channel to achieve the efficient mixing.