Understanding Structural, Chemical and Physical Variations in Lipid Nanoparticles

Lipid Nanoparticles have been around since the early nineties and have been successfully commercialized in the drug delivery space over the last two decades. Recently, the successful development of the SARS-Cov-2 vaccines established them as a promising technology for the targeted delivery of genes, DNA/RNA, and pharmaceutical products. Further they can be decorated with moieties that hold potential to tissue-specific delivery. Their manufacturing has unique challenges, as complex nanoscale physicochemical phenomena can impact their quality attributes such as size, drug loading, targeting agent availability, and particle morphology. Here, we present approaches that can help shed light to some of these nanoscale phenomena and enable study of 1) particle size and structure variations via Asymmetric Flow Field Flow Fractionation (A4F), 2) drug and targeting agent loading distribution via fractionation with size exclusion chromatography, and 3) real-time particle size measurement during manufacturing via Spatially Resolved Dynamic Light Scattering (SR-DLS). Our data show detection and quantitation of structural and compositional variability within LNPs. We also demonstrate the potential of the SR-DLS as a process analytical technology for real-time, in-line measurement of particle size integrated within manufacturing.