Figure 23.

Single water microdroplet held by the micropipette in heptol solution (1:1 mixture, by volume, of n-heptane and toluene). The water-oil interfacial tension of 40.3 ± 0.6 mN/m was directly measured from the geometrical shape of the microdroplet and the minimum pressure required to draw in the droplet to give a projection length inside the pipette of one pipette radius. With permission from Elsevier [11].