A central challenge with particle analysis in biotherapeutics is the wide size range of particles that may be present. Particles in these samples can be as small as a few nanometers (oligomer-sized protein aggregates, individual viruses) or large enough to be seen by the unaided eye (visible API aggregates). While several analytical techniques exist for particle monitoring, each can only analyze particles within a finite size range. Characterizing the entire particle content of a sample requires the use of several complementary analytical techniques to cover the potentially broad size range of particles that may be present.
Orthogonal techniques, or those that measure the same quantities as another technique but are based on a different measurement principle, are also often necessary in order to confirm measurements. While they can be time and sample-consuming, these multi-instrument particle monitoring strategies can provide a better understanding of a sample’s particle characteristics than a single measurement alone.
We recently presented an eChalk Talk webinar hosted by the American Association of Pharmaceutical Scientists (AAPS), titled "Orthogonal & Complementary Techniques for Subvisible Particle Characterization in Biotherapeutics".
This presentation discusses the concept of orthogonal and complementary techniques for particle analysis and why employing these is crucial to determine critical quality attributes (CQAs) in biopharmaceutical formulations. A case study is also presented to show how flow imaging microscopy can be paired with orthogonal and complementary techniques such as light obscuration and dynamic light scattering to help researchers characterize protein aggregation in drug products.
If you'd like to read more about the studies mentioned in the webinar, download our white papers on orthogonal and complementary techniques: