Vaccine Characterization with Cryo-TEM
Per-Particle Imaging Across Viral, Liposomal, and Protein Subunit Vaccine Platforms
Where a sample contains multiple particle types (adjuvants in addition to the nanoparticle in vaccine drug products, for example), cryo-TEM outperforms other analytical methods. Cryo-TEM imaging provides direct visualization of vaccine formulations in their near-native state, revealing critical quality attributes on a per-particle basis that cannot be captured by other techniques, all with only ~50μl of sample.
Throughout preclinical formulation optimization, in-process testing, stability, and release assays, cryo-TEM per-particle imaging is a crucial tool for analyzing vaccine stability and ensuring that final formulations maintain their integrity and efficacy throughout their shelf life.
Vaccine Platforms We Support
Liposomal Vaccines
Liposomal vaccine formulations can be produced in a variety of shapes and sizes. Cryo-TEM is the only technique that can directly visualize the presence of blebbing in liposomal formulations. Direct visualization of individual liposomes reveals particle morphology, lamellarity, nucleic acid payload distribution, and encapsulation efficiency, providing critical data for optimizing gene vaccine delivery.
Protein Subunit Vaccines
Vaccines present a purified antigen, such as a viral spike protein, often formulated with an adjuvant or displayed on a self-assembling nanoparticle scaffold. Cryo-TEM and negative stain TEM characterize antigen presentation and particle morphology, and can assess particle-adjuvant interactions, helping to optimize nanoparticle-based vaccine design.
What Cryo-TEM Reveals for Vaccines
Cryo-TEM nanoparticle characterization evaluates critical quality attributes including:
- Particle size distribution
- Antigen distribution on particle surfaces
- Morphology, including shape, circularity, and integrity
- Sample integrity and impurities
- Aggregation
- Interactions with and effects of adjuvant
- Cargo encapsulation and distribution
- Impact of storage conditions on particle structure, aggregation, and lamellarity over time
Stability Studies
Comprehensive analysis of the effects of storage conditions (buffer, pH, temperature, time) on formulation morphology is crucial for maintaining formulation stability. Stability studies with cryo-TEM imaging can be done at any phase.
Phase-appropriate, method-qualified or -validated characterization supports batch-to-batch reproducibility, scale up, comparability, and stability studies.
Our Vaccine Experience
We have imaged 2,900+ virus and VLP samples. Our team has partnered with vaccine developers on programs including SARS-CoV-2 nanoparticle vaccines, HPV characterization, tuberculosis vaccine formulation stability, and intranasal vaccine optimization.
