nor-MC3 is a novel ionizable lipid develoed by Nanovation, derived from the MC3 structural framework, characterized by two C17 alkyl chains (each containing two Z-geometry double bonds) conjugated to a 4-(dimethylamino)butanoate headgroup. Synthesized via a streamlined route involving Claisen condensation of methyl linoleate, hydrolysis/decarboxylation to generate a C17 ketone, reduction to the corresponding alcohol, and final esterification with 4-(dimethylamino)butanoic acid, nor-MC3 retains the ionizable amine functionality critical for pH-dependent nucleic acid binding and endosomal escape. Compared to the benchmark lipid MC3 (C18 chains), nor-MC3 demonstrates superior mRNA delivery efficiency in vitro (2-fold higher luciferase expression at 10 μg/mL mRNA) and enhanced in vivo biodistribution (higher liver and spleen targeting in mice). Notably, its shortened C17 chains challenge conventional assumptions about optimal hydrophobic chain length, offering improved synthetic scalability while maintaining or exceeding MC3's encapsulation efficiency (~95%), nanoparticle size (~80 nm), and low polydispersity (PDI ~0.08). For siRNA delivery, nor-MC3 achieves comparable EC₅₀ values (0.1644 μg/mL vs. MC3’s 0.1308 μg/mL), highlighting its versatility as a next-generation lipid nanoparticle (LNP) component for nucleic acid therapeutics.
