According to the researchers, the new scales can be used especially for determining proteins and other biomolecules better and more accurately than with current methods. By comparison, mass spectrometry determines the mass of millions of molecules based on their electrical charge, thus delivering an average mass. However, single molecules which deviate from this average are not detected. Such devices are also not suitable for measuring large biomolecules.

A protein molecule attached to the tiny weighbridge of the device alters vibration frequency, allowing the particle’s mass to be determined. In an initial test, the scientists weighed single antibodies from human blood, so-called M immunoglobulins, and identified them according to their mass differences. The new device is of interest to the field of medicine, but could also possibly be of interest for toxicology.

The researchers have published their device in "Nature Nanotechnology" (doi: 10.1038/nnano.2012.119)

Sources:

http://scinexx.de/newsletter-wissen-aktuell-15085-2012-08-29.html
http://www.nature.com/news/scaled-down-new-nano-device-can-weigh-single-molecules-1.11325