Advancing Liquid Front Shape Control in Capillary Filling of Microchannel via Arrangement of Microposts for Microfluidic Biomedical Sensors

초록

This paper presents the effect of micropost arrangements on the meniscus shape of the advancing liquid front for capillary filling in a microchannel of biomedical diagnostic sensors. Four different arrangements of cylindrical microposts inside microchannels including hexagonal array with smooth sidewall, hexagonal array with rugged sidewall, rectangular array with smooth sidewall, and rectangular array with rugged sidewall were considered. The meniscus shape of the fluid front were estimated by the volume-of-fluid based computational simulation and compared with experimental results. For hexagonal array, overall meniscus shapes of the advancing liquid front were concave form regardless of sidewall shape. On the other hand, capillary filling through rectangular arrangement of microposts occurred as a step-wise movement with maintaining the flat shape of the advancing liquid fronts. Sidewall microposts affected the capillary filling times rather than the meniscus shape of advancing liquid front. The shape of advancing liquid front and capillary filling time could be passively controlled by arrangement of microposts inside microchannel.

키워드