Mass spectrometry friendly pH-gradient anion exchange chromatography for the separation of full and empty adeno-associated virus (AAV) capsids

The proportion of full and empty capsids represents a critical quality attribute of adeno-associated virus (AAV)-based therapeutics. In this study, pH-gradient anion exchange chromatography was utilized for the separation of full and empty capsid species. The developed method allowed for applicability to multiple AAV serotypes and facilitated subsequent mass spectrometric detection of intact AAVs. This is the first study demonstrating generic applicability as well as mass spectrometric compatibility, allowing for a more sophisticated analysis of AAV-based gene therapy and paving the way for future developments in the field. Full/empty AAV capsid ratio assessment based on pH-gradient anion exchange chromatography with fluorescence detection interfaced to mass spectrometry.