Microscale Thermophoresis - Spectral Shift Analysis
Microscale Thermophoresis (MST) (coupled with Spectral Shift Analysis) is a technique that is able to analyze protein interactions in solution with minimal sample use. One of the molecules of interest is labeled with a fluorescent probe. The labeled material is titrated with a potential binding partner and both thermophoresis and fluorescence spectral shifts are measured. Thermophoresis measures motion of the labeled molecule in a temperature gradient. Additionally, the fluorescence spectral features of the probe are measured for subtle shifts. Spectral shifts combined with thermophoresis measurements as binding partner is titrated can be used to determine a dissociation constant (KD).
Installed in 2024, the Monolith X can use MST and SSA to determine KDs in the nM to mM range with low sample usage and can utilize multiple different strategies for probe labeling.