When the ability to improve or innovate a process is available it can bring peace of mind to the person who uses it daily. Implementing osmolality testing alongside routine pH and conductivity testing is an effective quality measurement for your manufacturing process.
Abstract: Biomanufacturing requires a complex and reproducible process to produce an effective biologic. The yield and quality of a biologic are highly dependent on the optimization of the downstream process. Buffers are used to maintain purification conditions and monitoring their concentrations provides assurance that they were properly prepared. The incorporation of process parameters, such as pH and conductivity, helps to maintain control of the process and prevent issues that could compromise the biologic. However, pH and conductivity measurements can be affected by environmental conditions and are not appropriate concentration measurements for all buffers (e.g. nonionic or weak electrolytes). This study investigated how osmolality compares to pH and conductivity across a wide range of concentrations of common downstream buffers. The buffer solutions were prepared gravimetrically and tested using a freezing point osmometer, pH probe and conductivity probe. The generated curves showed the distinct nature of each measurement. The study showed that osmolality is a reliable and sensitive measure of solute concentration compared to pH and conductivity. Together these process controls will help ensure optimal product quality and yield.
- Bratt, Jennifer, et al. Buffers in Biologics Manufacturing. BioProcess International 15.2(2017).
- Johnson, Michael W., et al. “Comparison of Concentration Measurement Technologies in Bioprocess Solutions.” Bioprocess International 13.9(2015).
- Challener, Cynthia. Behind the Scenes with Buffers. BioPharm International 28.2(2015).
- Gronemeyer, Petra, et al. Trends in Upstream and Downstream Process Development for Antibody Manufacturing. Bioengineering 1.4(2014).
- Leveling, Tony. The relationship between pH and Conductivity in a Lithium Contaminated, Deionized Water System. Pbar Note 675: The relationship between pH and Conductivity. Fermilab 2002.
- West, Jonathan, et al. “PH Measurement.” Visual Encyclopedia of Chemical Engineering, University of Michigan College of Engineering, 2018.
- West, Jonathan, et al. “Conductivity Meters.” Visual Encyclopedia of Chemical Engineering, University of Michigan College of Engineering, 2018.