Protein Unfolding or Denaturation Study with VROC Viscometer

Monoclonal antibodies (mAb) are recognized as important therapeutic biologics; they make it possible to target disease with fewer side effects.

Viscosity is an important parameter when optimizing injectable drugs. For therapeutic efficacy, mAb concentration must be maintained at a high level. However, viscosity increases when mAb concentration is increased. High viscosity causes problems when treating patients, because it’s hard to inject a patient with a highly viscous medicine without causing pain.

This makes mAb formulation challenging, as drug stability needs to be achieved with the lowest viscosity possible. By understanding viscosity, it is also possible to gain insight into the denaturation, unfolding, and/or stability of drugs.

This application note presents a study that used RheoSense’s VROC^® technology to capture the change in viscosity data when proteins are unfolded with the addition of urea. VROC^® is an accurate Viscometer-Rheometer-on-a-Chip, a scale viscosity sensor chip for small sample volume. It was an ideal viscometer, for this study because VROC^® viscometers can be used to investigate drug stability without diluting the solution. It also had a high resolution for distinguishing small increases in viscosity.

In this study, viscosities of the urea solution at varying concentrations were measured with VROC^® at 25 ±0.1 °C and compared with the values measured with the glass capillary viscometer.

For information on the results of this study, download the application note!