Flow Water Proton NMR: In-Line Process Analytical Technology for Continuous Biomanufacturing

Continuous manufacturing of biologics is one of the priorities of the biopharmaceutical industry. However, its wide spread implementation is hampered by a lack of noninvasive/nondestructive process analytical technology (PAT) systems capable of real-time in-line monitoring of product flow parameters, such as concentration and/or aggregate content. We have previously demonstrated that, under non-flow conditions, the water proton transverse relaxation rate, R2(1H2O), is sensitive to protein concentration and aggregate content in biopharmaceutical formulations. In the present work, we explored the potential of water proton NMR under flow conditions (flow-wNMR) to use R2(1H2O) as a quantitative indicator of protein concentration variations and aggregate levels in the process flow. We show that, under flow conditions, R2(1H2O) is sensitive to rather small changes in protein concentration (< 1 mg/mL), and is capable to detect variations in the aggregate content of < 1%. Our findings suggest that flow-wNMR could...