ABSTRACT

Microfluidics refers to the manipulation of liquid entities of subnanoliter volumes in channels that have at least one of their three dimensions in the order of micrometers (Whitesides 2006). Though, at conception, microfluidic applications were mainly targeted toward nonbiological fields such as analytical chemistry (deMello 2006), soon potentials of the subject were unleashed in the field of biology (Beebe et al. 2002). The use of microfluidics in solving biological questions has been catalyzed by two basic advantages that microfluidics offers. First, within microfluidic confinements, the volume requirement of liquid analytes is extremely low, implying a minimal volume requirement, which is essential for expensive and rare samples. Second, due to the augmented surface area-to-volume ratio in reduced length-scale, microfluidic devices offer enhanced performances, reduced reaction time, and higher sensitivity (McDonald et al. 2000, Thorsen et al. 2002) while dealing with surface immobilized reactants. Applying microfluidics in biology has revolutionized the paradigms of molecular biology, biochemistry, and bioengineering to such a great extent that relevant fundamental science and applications are classified by the researchers under the tenet of a separate subject named biomicrofluidics (Beebe et al. 2002). Its applications encompass almost every domain of biology such as protein engineering (Hansen et al. 2002, Mao et al. 2002), molecular cloning (Anderson et al. 2002, Ottesen et al. 2006), microbiology (Gu et al. 2004), and of course, cell biology (El-Ali et al. 2006, Okuyama et al. 2010, Wlodkowic and Cooper 2010), in which we are specifically interested. The basic objective remained the same behind all applications-how to scale down the laboratory techniques in size, essentially within a monolithic platform. In this way, applying microfluidics to biology has a similar impact to what silicon-based integrated circuits or so called very large scale integration (VLSI) technology had on the computation industry.