Macro mass photometry addresses analytical bottlenecks in adenovirus production
Adenoviral vectors are widely used to deliver cargo for a wide range of therapeutic products, including vaccines, gene therapies and cancer treatments. To create safe and efficacious end products, it is important to optimize adenovirus purification and measure key quality attributes in adenoviral vector samples. However, currently used techniques, like analytical ultracentrifugation (AUC), lack the speed and accessibility that is crucial for use in routine analysis.​​​​​​​​
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Macro mass photometry is a powerful tool for single-particle adenoviral vector analytics. Using light, it measures two parameters for each detected particle: Contrast (proportional to mass) and size, which allows it to differentiate and quantify different populations such as empty, full and helper adenoviruses. As macro mass photometry measurements take only minutes and use very small quantities of sample, they are ideally suited to optimize adenovirus production with repeated measurements at different points of the process.
Characterizing adenovirus packaging with macro mass photometry
The single-particle nature of macro mass photometry, combined with the two parameters it measures, allows it to readily detect the different populations present in a sample. In the case of adenoviral vectors, empty and full capsids have the same size but – due to their different masses – they can be distinguished using the contrast parameter measured by macro mass photometry, which is a proxy for mass.
The KaritroMP – Refeyn’s macro mass photometer – makes adenovirus packaging analysis easy by letting the user define ’gates’ (parameter limits) corresponding to the different populations of interest. Once these gates are defined, the KaritroMP can be used to measure the empty/full proportion of adenoviral vector samples in minutes, with little sample and by minimally trained staff. These strengths make mass photometry an ideal technique to quantify adenovirus packaging in adenoviral vector purification pipelines.
Macro mass photometry measurements of adenoviral vector samples with different empty/full ratios, including the defined parameter gates for full (A) and empty (B) capsids.
Quantifying adenovirus empty/full rapidly with macro mass photometry
This application note – created in collaboration with the Jenner Institute at the University of Oxford – shows how macro mass photometry can be used to quickly evaluate critical quality attributes of adenoviral vector samples, such as purity or adenovirus packaging. It also shows that macro mass photometry can distinguish adenoviral vectors from helper virus populations. In this application note, macro mass photometry results are compared to expected values as well as to results from orthogonal techniques, including AUC and negative stain electron microscopy (nsEM).
Additional resources​
WEBINAR​
Characterizing large viral vectors using macro mass photometry
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Accurate characterization of large viral vectors is a critical step in the development of viral vector-based gene therapies and vaccines. This webinar presents case studies and benchmark results on how the KaritroMP employs macro mass photometry to facilitate fast, straightforward, and qualitative analysis of single viral particles in cell and gene therapy applications. It also shows that it is well-suited for comparing different production and purification methods, as well as assessing batch-to-batch variations – ensuring the safety and efficacy of pharmaceutical products brought to market.
Macro mass photometry: A new way to characterize large viral vectors
Macro mass photometry is a revolutionary new technology for analyzing large viral vectors, such as adenoviruses (AdV) and lentiviruses (LVV). Returning results in minutes, it offers fast, simple, qualitative analysis to inform process development and optimization in the development of cell and gene therapies and vaccines.  Here, you can learn the basic principles of macro mass photometry and its applications.
More Application Notes
Browse through our catalogue of application notes highlighting some recent case studies featuring mass photometry.