Paper of the month: Isothermal chemical denaturation as a complementary tool to overcome limitations of thermal differential scanning fluorimetry in predicting physical stability of protein formulations
Determining which monoclonal antibody candidates or formulation conditions to progress which involves determining which combination of candidate and formulation will achieve the greatest conformational stability. Techniques like differential scanning fluorimetry are often used. However, the temperature dependance of certain buffers can lead to imprecise values for Tm being produced. In this month’s paper, they discuss the limitations of thermal approaches for measuring antibody stability and provide an alternative methodology which includes use of isothermal chemical denaturation.
Developing a typical formulation screening protocol for different buffers and pH values, they compare differential scanning fluorimetry and isothermal chemical denaturation techniques. The aim being to investigate isothermal chemical denaturation as a suitable protein stability indicating method for instances where thermal approaches where not appropriate.
Along with determining Gibbs Free Energy values using isothermal chemical denaturation, they also determine the change in Gibbs Free Energy with antibody concentration as a means of assessing aggregation propensity. They conclude that isothermal chemical denaturation should be used in conjunction with differential scanning fluorimetry to reduce sample amount requirements while providing prediction quality.
Selienov H, Markoja U, Winter G. Isothermal chemical denaturation as a complementary tool to overcome limitations of thermal differential scanning fluorimetry in predicting physical stability of protein formulations. European Journal of Pharmaceutics and Biopharmaceutics. 125: 113-125 (2018).