Biomedical Engineering Reference
In-Depth Information
Figure 6.49
Injection of the sample mixture in the FFF channel. Particles injected onto the column
without the field or flow turned on are evenly distributed across the column.
An example of a different type of chromatography columns is that of the pro-
teomic reactor [22]. Proteins are first digested into peptides; then all the peptides are
immobilized in a microfabricated (Figure 6.55) chromatography column. A flow of
acetonitril (CH3CN) is then used at different concentrations to elute progressively
the peptides. The eluted peptides are transported to a spray nozzle and sprayed into
the mass spectrometer.
Figure 6.56 shows the detection by the mass spectrometer of the well-known
peptide
b
-Galactosidase with its three characteristic peaks.
6.5 Cellular Microfluidics
Transport and manipulation of cells are becoming of utmost importance in today's
biotechnology. Many new devices have been recently developed to separate, con-
centrate, and immobilize cells in microsystems. In this chapter, we present some
remarkable features, such as single-phase flow focusing, pinched channels, bifurca-
tion channels, and ratchets for cell separation, and Dean flows for cell alignment
and recirculating chambers for cell trapping.
Figure 6.50
When a field is applied, the solute zone is compressed into a narrow layer against one
wall.
