Continuous mass photometry by single-molecule trapping.

Continuous mass photometry enables hour-long, mass-resolved observation of individual biomolecules tethered to supported lipid bilayers, with up to sub-kilodalton mass precision and millisecond temporal resolution.

• Why it matters: Direct, quantitative, time-resolved observation of biomolecular interactions is challenging, limiting how well complex mechanisms can be studied as they occur.
• What they did: The method continuously measures mass of single molecules and their complexes while tethered to supported lipid bilayers, achieving sub-kilodalton mass precision and millisecond temporal resolution over hour-long recordings.
• The result: This provides a quantitative time-resolved single-molecule measurement modality for studying complex biomolecular mechanisms in action.