advancing meniscus shapes alternated either concave shape (fig.1-b)
or convex shapes (fig.1-c). On the other hand, if diverging and
converging angle was steeper than 45∘, shape of advancing meniscus
was maintained as convex shape as shown in fig.1(d).Apparent
shape of advancing meniscus was dependent on side-wall shape of
microchannel, but interfacial angle between tangential direction of
side-wall and advancing meniscus was similar with 90∘. Shape of
advancing meniscus in microchannel depends upon surface energy
as well as side-wall shape. Interesting results provided design guideline
of microfluidic channels for biomedical diagnostic devices.