Adeno-associated viruses (AAVs) have become one of the most commonly used vectors to deliver gene therapies. As their use grows, so does the need for accurate, efficient AAV analytics. Mass photometry can monitor sample critical quality attributes (CQAs) throughout downstream workflows – accelerating manufacturing and process development, to ultimately help better therapeutics reach patients faster.
Quantification of AAV empty/full ratio
Mass photometry accurately measures empty/full AAV ratios, and resolves populations of partially filled and overfull capsids. It works by using light to measure the mass of each particle, which varies depending on the mass of the encapsidated genome.
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Figure: Mass photometry resolves empty, full and partially filled AAV subpopulations. Here, populations of empty and full AAV vectors form clearly visible peaks and represent the bulk of the sample, while partially filled capsids are distributed across an intermediate mass range. The mass photometry measurement was consistent with a SEC-MALS measurement of the same sample.
Agreement with orthogonal methods
Scientists working with AAVs must choose from among a range of options in the AAV vector analytics toolbox and it may be difficult to decide whether to prioritize accuracy or usability. With mass photometry, the difficulty disappears – mass photometers are highly accurate instruments that can be used over and over, throughout AAV purification processes.
Mass photometry has been proven to provide comparable results to SEC-MALS, cryo-TEM and analytical ultracentrifugation (AUC) while offering important practical advantages, including speed, ease of use and suitability for use in a GMP-compliant environment.
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Figure: Mass photometry (MP) results for AAV empty/full analysis are comparable to those obtained using AUC, a commonly used technology for AAV characterization. Source: Wagner et al., Int. J. Mol Sci, 2023.
Transforming analytical workflows for AAV purification
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Results in minutes
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Low sample requirement
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​Titer estimation
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Benchtop instrument
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Easy to use
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Any serotype
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Suitable for GMP-compliant environments
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Combining speed, ease of use and low sample requirements, mass photometry integrates seamlessly into workflows for the downstream processing of AAVs in gene therapy development and manufacturing. It is also suitable for GMP-compliant environments.
