Editing Molecular mass (section)

=== Mass photometry ===
Mass photometry (MP) is a rapid, in-solution, label-free method of obtaining the molecular mass of proteins, lipids, sugars and nucleic acids at the single-molecule level. The technique is based on interferometric scattered light microscopy.<ref>Young et al. (2018). Quantitative imaging of single biological macromolecules. Science 360, 423-427. DOI: https://doi.org/10.1126/science.aar5839</ref> Contrast from scattered light by a single binding event at the interface between the protein solution and glass slide is detected and is linearly proportional to the mass of the molecule. This technique can also be used to measure sample homogeneity,<ref>Sonn-Segev, A., Belacic, K., Bodrug, T. et al. Quantifying the heterogeneity of macromolecular machines by mass photometry. Nat Commun 11, 1772 (2020). https://doi.org/10.1038/s41467-020-15642-w </ref> to detect protein [[oligomerisation]] states, and to identify complex macromolecular assemblies ([[ribosomes]], [[GroEL]], [[Adeno-associated virus|AAV]]) and protein interactions such as protein-protein interactions.<ref>Soltermman et al. Quantifying protein-protein interactions by molecular counting using mass photometry.  Angew. Chem Int Ed, 2020, 59(27), 10774-10779</ref> Mass photometry can accurately measure molecular mass over a wide range of molecular masses (40 kDa – 5 MDa).