Researchers from Technion−Israel Institute of Technology and Tel-Aviv University have developed a new method to control electrically driven ion transport in microfluidic systems. The research, published in the journal Analytical Chemistry, describes the integration of individually addressable microvalves along a main microchannel coated with a thin layer of an ion-exchange membrane (IEM).
The method allows for the tunability of ionic transport between the solution within the microchannel and the IEM layer under an applied electric current, which can be locally adjusted by the deformation of the microvalve. This new approach provides a simple and robust way to control electrically driven ion transport in microfluidic devices, allowing for the implementation of new functionalities such as dynamic control over multiple ion concentration polarization (ICP) layers, multiplex sensing, suppression of biofouling, and plug dispersion, while maintaining the well-known application of microvalves as steric filtration.
The microvalves provide an effective and efficient way of controlling the electrically driven ion transport and could find applications in various fields. The researchers demonstrated the effectiveness of their method by creating preconcentrated molecule plugs and suppressing biofouling in lab-on-a-chip devices.
The ability to dynamically control electrically driven ion transport could lead to the development of new and innovative microfluidic devices, providing enhanced capabilities for analytical chemistry and biotechnology. The method's simplicity and robustness could also make it a useful tool for researchers and scientists working in these fields.
The researchers believe that the microvalve-based tunability method has the potential to be further optimized and adapted to suit specific applications and could be integrated into a wide range of microfluidic devices in the future.
Sabbagh, B.; Park, S.; Yossifon, G. Microvalve-Based Tunability of Electrically Driven Ion Transport through a Microfluidic System with an Ion-Exchange Membrane. Anal. Chem. 2023. DOI:https://doi.org/10.1021/acs.analchem.2c04600
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