Flow, focused aerodynamic focusing

FIGURE 3.2 Basic mechanism of aerodynamic focusing by air sheath flow. Undisturbed interaction of injected liquid flow with the channel walls and air sheath flow produces a stable two-phase flow configuration throughout the microchannel. Channel height is 100 pm [382]. Reprinted with permission from Springer Science and Business Media. 

A two-phase air-liquid flow was developed on a PDMS chip (see also Chapter 3, section 3.1.2). It was found that the focused two-phase flow was stable in hydrophobic channels (down to 6 mL/h) see Figure 8.38. Below this flow rate, the sample column no longer maintained its integrity and broke up. This method was used to provide aerodynamic focusing of myoblast cells (C2Ci2) for the flow cytometry study. The cells, which were labeled with Syto 9, was focused and counted in the chip at a rate of 100 cells/s [382]. 

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