This could move biology forward in the same way (that is, to the same extent) that PCR did. Chemists at UC Berkely and Lawrence Berkeley National Laboratory have devised a novel method of measuring protein-protein interactions at cell membranes. Microscopic glass beads are coated with artificial membranes in which functional receptor molecules are embedded, and the behaviour of the beads in response to the presence of various binding partners in the surrounding solution is monitored. From the Nature article (vol 427, pp. 139 - 141):

The behaviour of a colloidal system is driven by the pair interaction potential between particles. In the case of membrane-derivatized silica beads, the pair potential is dominated by membrane–membrane interactions. Two-dimensional dispersions of lipid-membrane-derivatized silica beads exhibit colloidal phase transitions that are governed by details of these membrane surface interactions. The collective phase behaviour serves as a cooperative amplifier that produces a readily detectable response from a small number of molecular events on the membrane surface. Using direct optical imaging, we observe multiple near-equilibrium phases and find that protein binding to membrane-associated ligands at densities as low as 10^-4 monolayer can trigger a phase transition. Statistical analysis of bead pair distribution functions enables quantitative comparison among different membrane systems and reveals subtle, pre-transition effects.

That translates to an extremely rapid, high-throughput method for screening ligand-receptor interactions that is sensitive in the picomolar range and requires nothing more complex than a light microscope. Cool.