In the biologics’ development process, the need for advanced analytical techniques has intensified with the growing complexity of therapeutic agents. Mass photometry has emerged as a powerful tool, revolutionizing the characterization of biomolecules. This innovative technology enables fast mass measurements of single molecules and adeno associated viruses (AAVs) in solution, providing valuable insights into their structural properties, interactions, and sample properties.
There are several distinct advantages that make mass photometry a valuable tool in biologics’ development. One key advantage is its label-free nature, eliminating the need for molecular modifications or immobilization that may alter biomolecular behavior. Another advantage is its low sample concentration requirements (100 pM – 100 nM for biomolecules, 1011 particles/mL for AAVs). Additionally, mass photometry has single-molecule resolution, capable of measuring the mass of single biomolecules or AAVs in solution. The single-molecule precision is invaluable in studying sample heterogeneity and structural characteristics that can significantly impact biologic efficacy and safety.
For the development of AAV-based gene therapies, mass photometry offers invaluable insights into the AAV samples. Capsid loading and sample purity are critical parameters for AAV sample quality control, and mass photometry can accurately distinguish AAV capsids with heterogeneous loading of genomic content (empty, full, partials), as well as provide a titer estimate of each population in a sample. Furthermore, mass photometry measurements take less than five minutes, require minimal training, and have exceptionally low sample requirements. This means that mass photometry can be employed even from the earliest stages of process development – when sample amounts and concentrations are particularly limited. The measurement of AAV empty-full ratios can now be also applied to GMP-regulated environments with new software solutions, compliant with FDA 21CFR11 and EU Annex 11.
In conclusion, mass photometry addresses several key challenges in AAV sample characterization workflows. By providing rapid insight into sample properties, it removes the bottlenecks associated with current gold-standard methods for AAV sample analytics.