Lab-on-a-chip microfluidic devices have immense potential for biomedical and chemical research, however typically they are specific for each application and cannot be reconfigured. As each assay relies on a prefabricated, complex microchip specifically designed for a unique use, each application requires a completely new chip. The ability to reliably direct flows in an unconstrained liquid film without the need of a patterned microchip would facilitate the development of microchips that can be easily reconfigured for multiple possible assays.
Researchers at the University of Michigan have developed a way to generate a controlled flow in unconstrained liquid film without the need of a patterned microchip. The flows are based on creating the gradients in surface tension (i.e., the Marangoni effect) caused by thermal singularities. The Marangoni effect results in high speed flow patterns that vary from surface doublets to toroids. University of Michigan researchers have shown how some of these patterns can be used for trapping, mixing, and spinning aqueous microdroplets encapsulated in the same medium. The flows are driven by temperature variations on the surface of a thin liquid film. When microscale heat sources are used to create controlled temperature variations, both the speed and the geometry of the flow region can be well controlled. As a result, various flows can be tailored to accomplish a number of chemical analysis procedures, including single molecule detection.
Applications and Advantages
- Re-configurable microchips
- Single molecule detection applications
- Reconfiguration of the chip real time to-nl-allow for performance of multiple different-nl-assays