A Scale for Weighing Single Molecules

Imagine a scale that can weigh a single molecule, with a precision measured in the mass of a proton. California Institute of Technology researchers have built it: a digital device that can weigh single proteins (or nanoparticles) as small as 1 megaDalton (about 1.6 attogram).

Using standard CMOS manufacturing techniques, Michael L. Roukes’s Nanoscale Systems lab (in collaboration with CEA-LETI in Grenoble) fabricated what they call a nanoelectromechanical systems-based mass spectrometer (NEMS-MS), a vibrating-beam scale less than 10 micrometers long.  (They describe the device in the current issue of Nature Nanotechnology.) [read more..]