Protein characterization includes primary, secondary, tertiary, and quaternary structural analysis, with secondary structure providing a direct representation of the spatial arrangement around the peptide backbone. Monitoring this level of protein folding is important for preserving protein critical quality attributes. Many of the tools typically involved in measuring protein structure are destructive techniques, meaning the samples cannot be recovered or reused once analyzed. For samples that are limited in quantity or precious in nature, the inability to further analyze them is a significant drawback. The AQS³pro, manufactured by RedShiftBio and powered by Microfluidic Modulation Spectroscopy (MMS), is a novel infrared spectroscopy tool that measures protein secondary structure in a non-destructive manner, thus enabling subsequent characterization and analysis.
This study focuses on lysozyme as a test case to demonstrate robust protein analysis using MMS, successful re-collection post-analysis with some dilution, and intact structural integrity. Additionally, this study highlights the ability to re-concentrate post-MMS collected samples with a recovery rate of approximately 90% and similarity of >98% relative to the initial protein preparation.