Freeze Thaw Cycles
Repeated freezing and thawing of biomolecules such as proteins can lead to significant denaturation even in the presence of cryoprotectants, therefore aliquotation of protein preparations is generally recommended. Low sample quality, e.g. due to repeated freeze- thaw cycles, can in turn significantly affect reproducibility and quality of downstream characterization steps such as binding assays. It is especially recommended to test if repeated cycles of freezing and thawing of the Target protein affect the result of an interaction measurement. This can be done by comparing the result of a Binding Check experiment for different aliquots.
Particularly, protein Aggregation is an issue that can be detrimental to data quality. Determining protein stability and quality first can therefore save both time and money e.g. in subsequent screening campaigns. NanoTemper’s instrument Tycho NT.6 (see Tycho NT.6 on nanotempertech.com) can be used to determine optimal handling conditions by quantifying the fraction of unfolded protein in a sample within seconds.