We introduce an online synthesis flow, focusing primarily on the virtual topology and operation binder, for digital microfluidic biochips, which will enable real-time response to errors and control flow. The objective of this flow is to facilitate fast assay synthesis while minimally compromising the quality of results. In particular, we show that a virtual topology, which constrains the allowable locations of assay operations such as mixing, dilution, sensing, etc., in lieu of traditional placement, can significantly speed up the synthesis process without significantly lengthening assay execution time. We present a base virtual topology and show how it can be leveraged to reduce algorithmic runtimes and guarantee rout ability. We later present several variations of the virtual topology and present experimental results demonstrating best-design practices. We present two binding solutions. The first is a left-edge binding algorithm, while the second is a more intelligent path-based binding algorithm that leverages spatial and temporal locality to produce superior results. © 2013 IEEE.

This paper introduces a field-programmable pin-constrained digital microfluidic biochip (FPPC-DMFB), which offers general-purpose assay execution at a lower cost than general-purpose direct addressing DMFBs and highly optimized application-specific pin-constrained DMFBs. One of the key cost drivers for DMFBs is the number of printed circuit board (PCB) layers, onto which the device is mounted. We demonstrate a scalable single-layer PCB wiring scheme for several FPPC-DMFB variations, for PCB technology with orthogonal routing capacity of at least three; for PCB technology with orthogonal capacity of two, more PCB layers are required, but the FPPC-DMFB retains its cost advantage. These results offer new insights on the relationship between PCB layer count, pin count, and cost. Additionally, to reduce the execution time of assays on the FPPC-DMFB, we present efficient algorithms for droplet routing, with and without contamination removal via wash droplets.

Routing-based synthesis for digital microfluidic biochips yields faster assay execution times compared to module-based synthesis. We show that routing-based synthesis can lead to deadlocks and livelocks in specific cases, and that dynamically detecting them and adjusting the probabilities associated with different droplet movements can alleviate the situation. We also introduce methods to improve the efficiency of wash droplet routing during routing-based synthesis, and to support nonreconfigurable modules, such as integrated heaters and detectors. We obtain increases in success rates when dealing with resource-constrained chips and reductions in average assay execution time.