- Hydrolytic degradation of polysorbate during 2–8°C storage of monoclonal antibody drug products has been attributed to residual enzymes
- A fluorescence, plate-based esterase activity assay was developed as a monitoring and characterization tool for polysorbate degradation
- High-throughput method allows for rapid characterization of monoclonal antibody samples
- Esterase assay correlates directly with polysorbate degradation
Hydrolytic degradation of polysorbate during 2–8°C storage of monoclonal antibody drug products has been attributed to residual enzymes from
bioprocessing steps. Robust detection of esterase activity using non-polysorbate surrogate substrates can provide an alternate and faster
method to assess polysorbate degradation risk, if the correlation between the esterase activity and polysorbate degradation is established. A
general esterase activity assay, utilizing 4-methylumbelliferyl caprylate (MU-C8) as the esterase substrate, was developed as a monitoring and
characterization tool during bioprocess development of monoclonal antibodies. The assay was first assessed for substrate, inhibitor and pH
specificity using both model enzymes and purified protein samples. In addition, the assay was tested to understand sample matrix effects on
activity rates. The use of this high-throughput method allows for rapid characterization of protein samples in under three hours. The esterase
activity also correlated directly with polysorbate degradation, providing valuable information on polysorbate degradation risk throughout drug
development.
Adithi Bhargava, Technical Development Scientist, Genentech
