nanoDSF is a novel label-free method used for thermal and chemical unfolding experiments to quantify the melting temperature for a protein. In addition, nanoDSF can determine the colloidal stability (aggregation onset temperature) by backreflection optics
Studying conformational stability of proteins
Intrinsic tryptophan fluorescence of proteins is strongly dependent on the 3D-structure hence the surrounding of the amino acid. Using chemical denaturants or a thermal gradient, protein structures are unfolded, leading to changes in intrinsic fluorescence and/or fluorescence emission peak shifts. nanoDSF monitors these fluorescence changes with high resolution and reveals even multiple unfolding transition points (protein melting temperatures). nanoDSF is, therefore, highly applicable in antibody engineering, membrane protein characterization and protein quality control. Principle behind the nanoDSF: Increasing temperature causes protein unfolding that can be assessed by monitoring changes of tryptophan fluorenscence at 330 and 350nm wavelength.
Studying colloidal stability of proteins
To detect protein aggregation, the Prometheus NT.48 employs a backreflection optics. Light passes through a capillary containing the protein sample of interest. If the protein is not aggregated, all incident light passes the capillary, is then reflected by the capillary tray and quantified by the detector. If the protein sample contains aggregation particles, the incident light is scattered by the particles. The loss of light therfore is a precise measure for protein aggregation.
If you would like to know more on the technical setup of the nanoDSF, please read here.