Will coffee rings find a place in the laboratory?

Microfluidics is a hot topic and one we have previously written about in this column. We have covered everything from microchips to rethinking the glucometer. Recently, we rediscovered a 2011 report (1 ) that takes the ideas behind microfluidics—manually or passively manipulating a fluid, particularly to identify what is in it—and suggests applying new knowledge we have about the ever-familiar “coffee ring effect” to clinical needs. The researchers’ disarmingly simple idea is what we tackle here.