Immobilization method of escherichia coli for microfluidic application

Escherichia coli (E. coli) has been used extensively in various industrial and scientific applications but has not been used widely for microfluidic applications because it is difficult to immobilize properly to a device. Here, we describe the development of an E. coli immobilization method for microfluidic devices using single-walled nanotubes (SWNTs) and dielectrophoresis (DEP) force. SWNTs and E. coli were aligned between two cantilever electrodes by a positive DEP force, forming a film of SWNTs with attached E. coli. For a microfluidic device, our one-step immobilization method has many advantages such as site-specific immobilization, easy density and shape control, an electrically connected structure from the electrodes to the E. coli, and rapid processing.