Differential scanning fluorimetry (DSF)
Coriolis Pharma is specialized in providing analytical services for protein stability testing, including differential scanning fluorimetry (DSF).
DSF is used to monitor thermal transitions of proteins, such as unfolding, in the presence of a fluorescent dye. The dyes that can be used for DSF are highly fluorescent in non-polar environment, i.e. in hydrophobic pockets of (partly) unfolded proteins, whereas the fluorescence is quenched in aqueous solution and/or in presence of native protein.
A common application of DSF is the determination of the conformational stability of proteins. When the fluorescence intensity of the dye in presence of protein is plotted as a function of the temperature, the apparent melting temperature (Tm) of the protein can be derived from the inflection point of the resulting sigmoidal graph. Also, information can be gained indicating cooperative (two-state) or complex unfolding transitions in multi-domain proteins.
DSF allows rapid analysis of multiple samples in parallel under identical conditions, e.g., within a formulation development study using different stabilizing excipients, thus being a valuable tool for formulation screening studies. DSF may be considered as an alternative approach to assessment of Tm by µDSC.
At Coriolis we employ an Analytik Jena qTower2 instrument with 96-well plates for DSF analysis. In the course of method development we propose cross-correlating the findings against results from µDSC measurements. A relevant publication ("High-throughput melting-temperature analysis of a monoclonal antibody by differential scanning fluorimetry in the presence of surfactants.") has recently been published.