Nanoelectromechanical systems (NEMS) resonators can detect inertial mass with exceptional sensitivity. Previously, mass spectra from several hundred adsorption events were assembled in NEMS-based mass spectrometry using statistical analysis. Here, we report the first realization of single-molecule NEMS-based mass spectrometry in real time. As each molecule in the sample adsorbs upon the NEMS resonator, its mass is determined by continuously tracking two driven vibrational modes of the device. We demonstrate the potential of NEMS-based mass spectrometry by analyzing IgM antibody complexes. NEMS-MS is a unique and promising new form of mass spectrometry: it can resolve neutral species, provides resolving power that increases markedly for very large masses, and allows acquisition of spectra, molecule-by-molecule, in real time.

Light refreshments will be served after the seminar.