Thermal Stability as a Function of pH and Concentration
May 15, 2012
The thermal stability of a protein formulation depends not only on the intrinsic properties of the protein itself, but also on buffer composition and the concentration at which the protein is formulated. With the DynaPro Plate Reader, a variety of conditions can be dispensed into 96-, 384-, or 1536-well plate formats to quantify protein stability as a function of temperature, pH, concentration, and excipient profile.
In this experiment, a monoclonal antibody was prepared in bis-tris-propane buffer (50 mM) at pH 8.5 and pH 9.5 and concentrations of 0.47-15 mg/mL to identify the thermal stability of the protein at twelve different conditions. For each condition, 20 ?L of solution was loaded in triplicate into a 384-well microtiter plate, and each well was covered in paraffin oil to prevent evaporation. The hydrodynamic radius of the antibody in each well was measured as the temperature of the entire plate was increased from 25 to 85 C, at a rate of 0.1 C/min. Read the rest of the app note here.