AA2 lipid is an innovative amino alcohol-derived ionizable lipid designed for optimized mRNA delivery. Its unique structure includes a hydroxyl-containing headgroup that enhances mRNA binding through hydrogen bonds and a branched ester tail (R2) that promotes a cone-shaped architecture, facilitating efficient endosomal escape. Formulated into lipid nanoparticles (LNPs) with a size of 108.6 ± 3.7 nm and a polydispersity index (PDI) below 0.3, AA2 achieves high mRNA encapsulation efficiency (89.0 ± 1.4%) and an ideal pKa of approximately 6.2, ensuring effective endosomal release.In vivo studies demonstrate that AA2 LNP-encapsulated spike mRNA elicits 4.7-fold higher IgG titers and robust CD8+ T-cell responses (characterized by IFN-γ+, TNF-α+, and granzyme B+ markers) compared to SM-102/ALC-0315 LNPs. Notably, AA2 exhibits minimal off-target accumulation, with low biodistribution in the liver and spleen. Its slightly positive surface charge (+3–5 mV) enhances cellular uptake, while the biodegradable ester structure ensures metabolic clearance, reducing potential toxicity.

Providing storage is as stated on the product vial and the vial is kept tightly sealed, the product can be stored for up to 24 months.
Wherever possible, you should prepare and use solutions on the same day. However, if you need to make up stock solutions in advance, we recommend that you store the solution as aliquots in tightly sealed vials at -20°C. Generally, these will be useable for up to one month. Before use, and prior to opening the vial we recommend that you allow your product to equilibrate to room temperature for at least 1 hour.

LNP-RNA-mediated antigen presentation leverages SARS-CoV-2-specific immunity for cancer treatment Y Xue, X Hou, Y Zhong, Y Zhang, S Du, DD Kang… - Nature Communications, 2025