Recent progresses in microfabricating perfluorinated polymers (Teflons) and the associated new applications in microfluidics
During the past two decades, microfluidics has become an enabling technology in many fields, including cell-biology, biophysics, biochemistry, optofluidics, etc. In the meantime, researchers are paying more attention to device materials because of the problems and unique functions they brought. As the most popular material in current microfluidic research, polydimethylsiloxane (PDMS) also has some drawbacks, such as absorption of small molecules and poor organic solvent compatibility. Thus, perfluorinated polymers (Teflons), which retain most advantages of PDMS but also has excellent inertness and anti-fouling properties, came into researchers’ perspective. After the initial period when liquid Teflon were directly coated on PDMS, whole-Teflon microfluidic chips were successfully fabricated and performed excellently in long-term cell culture, organic solvent-involved synthesis, etc. Since then, materials such as metals, biomolecules and other plastics have been integrated into Teflon chips and expanded their use to electrochemical sensing and immunoassay. Furthermore, perfluoropolymers have also been broadly used to assist mold release due to their nonstick property. Aiming to illustrate this progress, current review focuses on the recent development of Teflon microfabrication and applications in microfluidics, and provides critical discussion on this trend.