Microfluidics-Based Biochips: Technology Issues, Implementation Platforms, and Design-Automation Challenges

Abstract

Abstract-Microfluidics-based biochips are soon expected to revolutionize clinical diagnosis, deoxyribonucleic acid (DNA) sequencing, and other laboratory procedures involving molecular biology. In contrast to continuous-flow systems that rely on permanently etched microchannels, micropumps, and microvalves, digital microfluidics offers a scalable system architecture and dynamic reconfigurability; groups of unit cells in a microfluidics array can be reconfigured to change their functionality during the concurrent execution of a set of bioassays. As more bioassays are executed concurrently on a biochip, system integration and design complexity are expected to increase dramatically. This paper presents an overview of an integrated system-level design methodology that attempts to address key issues in the synthesis, testing and reconfiguration of digital microfluidics-based biochips. Different actuation mechanisms for microfluidics-based biochips, and associated design-automation trends and challenges are also discussed. The proposed top-down design-automation approach is expected to relieve biochip users from the burden of manual optimization of bioassays, time-consuming hardware design, and costly testing and maintenance procedures, and it will facilitate the integration of fluidic components with a microelectronic component in next-generation systems-on-chips (SOCs).

A fast routability- and performance-driven droplet routing algorithm for digital microfluidic biochips

“…Although they have been successfully applied to many biological applications, their lack of reconfigurability makes unsuitable for large scale systems. Recently, the second-generation (digital) microfluidic biochips, which are based on the manipulation of discrete microliter or nanoliter liquid particles (the droplets), have been proposed [9]. Such droplets are manipulated independently by the electrohydrodynamic forces generated by an electric field [2].…”

“…One of the critical steps in DMFB physical design is the droplet routing problem [9]. The main challenge of droplet routing is to ensure the correctness of a bioassay; the fluidic property which avoids unexpected mixing among droplets needs to be satisfied.…”

Microfluidics:A Boon for Biological Research

“…Secondly, device performance is affected due to the coupling of different energy domains (electrical, fluidic, thermal, etc.) and the mechanisms for device failure due to this reason are not yet fully understood 54 . Thirdly, when working with biological materials such as cells, microchannels tend to get clogged irreversibly.…”

A model for the determination of the dimensions of dents for jagged electrodes in electrowetting on dielectric microsystems

“…We set the values of the contact angles 1 = 80°and 2 = 110°corresponding approximately to water on Teflon®. Our first example is that of the electrode design by Duke University, 11 shown in Fig. 6͑a͒.…”