An Empirical Phase Diagram–High‐Throughput Screening Approach to the Characterization and Formulation of Biopharmaceuticals

The complexity of proteins usually requires the use of multiple, moderate resolution experimental techniques to provide an information-rich picture of their structure and stability. Here we describe a technique known as the empirical phase diagram (EPD), which can be used to present such multidimensional data in picture form. Data from various spectroscopic, hydrodynamic, and calorimetric methods, among others, are created in matrix form and converted to a colored picture as a function of variables such as temperature, pH, ionic strength, etc. Additional methods such as radar charts and Chernoff faces are also discussed. The use of EPDs in the characterization and formulation of biomolecules is described. Further methods based on machine learning are also considered. A wide range of examples are employed to illustrate the power and utility of these approaches.