We report the successful realization of a microfluidic chip with switching and corresponding inverting functionalities. The chips are identical logic control components incorporating a type of smart colloid, giant electrorheological fluid (GERF), which possesses reversible characteristics via a liquid-solid phase transition under external electric field. Two pairs of electrodes embedded on the sides of two microfluidic channels serve as signal input and output, respectively. One, located in the GERF micro-channel is used to control the flow status of GERF, while another one in the ither micro-fluidic channel is used to detect the signal generated with a passing-by droplet (defined as a signal droplet). Switching of the GERF from the suspended state (off-state) to the flowing state (on-state) or vice versa in the micro-channel is controlled by the appearance of signal droplets whenever they pass through the detection electrode. The output on-off signals can be easily demonstrated, clearly matching with GERF flow status. Our results show that such a logic switch is also a logic IF gate, while its inverter functions as a NOT gate. © The Royal Society of Chemistry 2010.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): SA-C0040, UK-C0016
Acknowledgements: This publication is based on work partially supported by Award No. SA-C0040/UK-C0016, made by King Abdullah University of Science and Technology (KAUST), Hong Kong RGC grants HKUST 603608, and the Nanoscience and Nanotechnology Program at HKUST. Useful discussion with Casey Glick is acknowledged.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.