High-sensitivity Orbitrap mass analysis of intact macromolecular assemblies

Nat Methods. 2012 Nov;9(11):1084-6. doi: 10.1038/nmeth.2208. Epub 2012 Oct 14.


The analysis of intact protein assemblies in native-like states by mass spectrometry offers a wealth of information on their biochemical and biophysical properties. Here we show that the Orbitrap mass analyzer can be used to measure protein assemblies of molecular weights approaching one megadalton with sensitivity down to the detection of single ions. Minor instrumental modifications enabled the measurement of various protein assemblies with outstanding mass-spectral resolution.

MeSH terms

  • Chaperonin 60 / chemistry
  • Immunoglobulin G / chemistry
  • Macromolecular Substances / chemistry*
  • Mass Spectrometry / methods
  • Molecular Weight*
  • Proteomics / methods
  • Spectrometry, Mass, Electrospray Ionization / instrumentation
  • Spectrometry, Mass, Electrospray Ionization / methods
  • Tandem Mass Spectrometry


  • Chaperonin 60
  • Immunoglobulin G
  • Macromolecular Substances