Abstract
This thesis presented a multi-function microfluidic array that is capable of programmably metering, entrapping, coalescing, addressably storing and retrieving droplets, which could potentially serve as reactors for continuous tracking and multi-step processing. A PDMS multi-layer chip with specially designed fluidic-channels dynamically re-configured by pneumatically-actuated diaphragms is utilized to realize various droplet manipulation schemes. We have fabricated the prototype demonstration that droplets with desired volumes and compositions are generated. Once droplets are formed, their motions are coordinated by a 2-D multiplexing scheme, which exploits the bi-directional movement of diaphragms to implement a random-access microarray, which means our microarray chip could be selectively stored, and retrieved from a 4×4 array, which employs just 4 (=2×log24) control inputs for the operation. With droplets functioning as micro-reactors, have the advantages such as low sample consumption and high reaction that the proposed random-access storage array could potentially serve as a chip for high throughput and multi-step reaction control. The chip is expected to significantly accelerate the progress in drug discovery, and various chemical and biological screening and synthesis. There are three accomplishments have been achieved in this thesis paper : (1) 2-D multiplexing can be largely facilitated using bi-directional diaphragm valves, (2) N×N multiplexing of droplets could be realized utilizing only 2×log2N control inputs and (3) a fully addressable, random-access array can be accomplished employing multi-layer microarray PDMS chip.