Automatic mixing of highly viscous bio-samples with orbital shaking using micro-channels

Automatic mixing of highly viscous bio-samples using orbital shaking and micro-channels is considered. Existing methods for mixing bio-samples for life science applications use micro-well and micro-stirrer which are ineffective for highly viscous materials at the microliter or nanoliter level. Our method mixes viscous bio-samples in micro-wells using orbital shaking and micro-channels. To understand the mixing process, the design of a small block, which is installed in the middle of the micro-well, with the micro-channels is presented. The model of the micro-channels under orbital shaking is developed. Reynolds numbers to the flow of viscous bio-samples in the micro-channel are calculated and the mixing process is analyzed. The experiment results of mixing monoolein with water are presented. In each trial, X-ray diffraction is used to evaluate the results which confirm that the proposed approach is valid, and reveal the relationship between the shaking speed and duration for a homogeneous mixing.