The biopharmaceutical industry characterizes and quantifies aggregation of protein therapeutics using multiple analytical techniques to cross validate results. Here we demonstrate the use of electrospray-differential mobility analysis (ES-DMA), a gas-phase and atmospheric pressure ion-mobility method for characterizing protein aggregates. Two immunoglobulins (IgGs) are systematically heat treated to induce aggregation and characterized using size exclusion chromatography (SEC) and ES-DMA. Although ES-DMA is a gas phase characterization method, we find that aggregation kinetic rate constants determined by ES-DMA to be in excellent agreement with those determined by SEC. It is also found that ES-DMA is more capable of resolving aggregates of IgGs than SEC. The higher resolution of ES-DMA and a limit of detection two orders of magnitude lower than the SEC potentially make it a powerful tool for characterization of nascent protein aggregates in the biopharmaceutical industry.
Citation: Journal of Pharmaceutical Sciences
Pub Type: Journals
immunoglobulins, heat-treat, ES-DMA, SEC, rate constant, protein aggregates