The world’s most sensitive scales can now measure a mass of just one zeptogram (10-21 grams) – roughly the mass of a single protein molecule.
Researchers can measure masses of one attogram (10-18 grams), which is equivalent to a cluster of gold atoms, by placing an object on a vibrating silicon blade and noting how the frequency of vibrations changes.
By making a shorter blade out of much stiffer silicon carbide, a team at the California Institute of Technology in Pasadena was able to boost the resonant frequency of the vibrations sixfold, allowing the detection of masses 1000 times…


