Abstract
Antibody drugs have heterogeneity, and therefore, the evaluation of the physical properties of antibodies are required to obtain the accurate amount of the target protein as an active ingredient and its impurities for the control of drug substances. Furthermore, it is also important to investigate the physical properties of the antibody that affects the stability of the pharmaceutical product, such as the antibody characteristics that suppress the aggregation in the phase of the development of new antibody candidates. In this review, we will introduce several techniques to evaluate the physical properties of antibody, which is necessary for the quality control of the drug substance, namely, the protein concentration, viscosity, and its binding ability to antigens and receptors, as well as the physical properties of antibody that affect the stability of the biopharmaceutical products, namely, structural stability, colloidal stability, surface potential, and particle size, with brief introduction of the implication of each parameters.
