"One of the driving concepts in biology these days is an idea insiders call ""The Movie"": a depiction of a cell in which the action of all life’s molecules--genes, enzymes, nutrients and the like--can be seen in vivid detail, close up,and in real time. The movie doesn’t exist yet, but talented technologists including Jason Shear are working hard to bring it into focus. Combining a grab bag of advanced imaging technology and analytical methods, Shear is developing a system to record chemical communiqués between neurons as they happen--for instance measuring the neurotransmitter serotonin as it’s secreted across a living nerve cell junction, or synapse. The design will use robotically controlled silica needles, nanometers in diameter, to sample the chemicals present inside lab-grown neurons, then measure them with an ultrasensitive detection method called multiphoton excited fluorescence.
If Shear’s approach works, it will produce scenarios guaranteed to keep neurobiologists riveted. Shear hopes the denouement will be a better understanding of the chemical basis of learning. This work-in-progress isn’t Shear’s first clever invention; another scheme used nerve cells themselves as molecular detectors, and with colleague Eric Anslyn he’s developed a chemical-sensing ""Electronic Tongue.""