WHAT DOES NANOFLUIDICS HAVE TO OFFER?
PLENTY, SAY EXPERTS.
At nanoscale dimensions, different physical phenomena start to dominate; this leads to new scientific insights and applications.
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s it a case of proving how low one can go, or does nanofluidics have a purpose? We’re already well versed in the advantages of microfluidics—limited reagent consumption, quick reaction times, and high throughput. Does going into the realm of nanofluidics achieve anything more? Researchers in the field give the impression that the party only really gets started once you go from the microscale to the nanoscale. “Going from bulk to micro, nothing really changes. Sometimes it’s a misconception that going to micro, things change. No, they don’t,” says Robert Austin of Princeton University. “But when you go from micro to nano, it’s not just hype at that point.
Rajendrani Mukhopadhyay
There really are new areas of physics, materials science, and chemistry that come in at the nanoscale.” Part of the excitement stems from the fact that different physical phenomena start to emerge at the nanoscale, opening up the opportunity to learn new science. The rest comes from the promise of novel applications at the single-molecule level. “It’s a totally new toolbox that one can use to study and manipulate individual biological molecules,” says Peidong Yang at the University of California, Berkeley. “You can also carry out individual molecular reactions within these nanofluidic environments.” Experts emphasize that nanofluidics isn’t brand-new. Even if we don’t realize it, we’ve been using materials that embody the principles of nanofluidics for quite a while. Harold Craighead of Cornell University says, “I have a water filter that I use when I go camping—which is a very simple sorter of bad things out of good things—and it has nanofeatures in it. We don’t necessarily know how these things work in detail, because we’ve empirically derived how to use these porous materials.” But, as Craighead explains, those materials have the same issues with surface area, diffusion, and flow as in nanofluidics. The difference is that research into nanofluidics can result in structures that are engineered to have more precisely controlled behaviors. “We can make more complex devices that could do more integrated processing and analysis,” he says.
What are we talking about? Before we go any further, a definition of nanofluidics is in order. The term has been used to refer to experiments done with nanoliter volumes as well as those carried out in devices with nanosize features. Experts interviewed for this article define nanofluidics as the study of the phenomena that arise in fluidic systems when at least 1 dimension of a device is
