Quantitation of different capsid species in viral-vector gene-delivery drugs, including recombinant adenoassociated virus (AAV) therapies, is essential for proper assessment of critical quality attributes before regulatory approval and during commercial production. If rAAV full-capsid percentages are maximized, and variants such as empty or partially-filled capsids are reduced as much as possible, then potency is increased for improved dosing and tolerance outcomes. Traditionally, characterization of AAV purity with respect to empty, full, and other variants has been performed by techniques such…