Characterization of Acoerela AcoRL-600 Reference Liposomes using Analytical Ultracentrifugation

The increasing use of liposomes and lipid nanoparticles (LNPs) for drug delivery requires comprehensive characterization of LNP properties in a physiological solution environment to ensure efficacy and patient safety. This study focuses on commercially available Acoerela AcoRL-600 ^™ reference liposomes, which are used to to optimize instrument settings and provide a reliable reference for fluorescence-based analyses of LNPs such as extracellular vesicles (Evs) and lipid-based therapeutics. Analytical ultracentrifugation (AUC) experiments were performed using three detection modes: UV/visible absorbance optics in intensity mode, Rayleigh interference and fluorescence emission. The results show that caution must be exercised when interpreting fluorescence data acquired for liposomes as the smaller particles may not be properly represented due to the effects of quenching. This finding applies not just to AUC experiments, but should also be considered for flow cytometry using fluorescent dyes to label LNPs, liposomes and extracellular vesicles.