Movie S3.

Adding fluid via a liquid bridge to a chamber (the movie runs in real time, and frames from it are reproduced in Fig. 3B). A 16 x 8 grid (2.25 x 2.25 mm chambers, rectangular dish) was made using medium, and red and blue dyes delivered to chambers. Between 0-13 s, medium is continuously ejected from the pipet tip, which is immersed in FC40 and positioned above the recipient chamber containing red dye. The pipet is a hydrophilic tube with a hydrophobic sleeve at the end. At 0 s, ejected medium begins to form a bubble at the end of the tip. By 9 s, the bubble has grown sufficiently to touch the surface of the chamber, and a liquid bridge forms. Note that there is no detectable transfer upwards of red dye through this bridge. By 11 s, the bridge has broken, and no red dye can be detected in the bubble on the tip. After 13 s, a new bridge has formed, and again no dye is being transferred upwards. The tip will now move to a new position above another chamber, and deliver medium to it. This movie indicates that essentially no red dye will be transferred between chambers during this process.