Synthesis and Evaluation of Novel Ionizable Lipids Based on the Tris(hydroxymethyl)aminomethane (TRIS) Scaffold for Lipid Nanoparticle Development and mRNA Delivery

Ionizable lipids are versatile components in mRNA delivery, protecting genetic material and facilitating cytosol transport. Despite their established importance, we hypothesized that novel ionizable derivatives could be developed using a tris(hydroxymethyl)aminomethane (TRIS BASE) scaffold. To explore this hypothesis, we disclose herein a new route to synthesize primary (4), secondary (6), and tertiary (8) aminolipids. The synthesis begins with protection of TRIS BASE (95%), followed by triesterification with oleoyl chloride to form intermediate 3 (85%). Deprotection of 3 provides aminolipid 4 (85%). Alternatively, methylation of 3 yields 5 (35%), which after deprotection gives aminolipid 6 (80%). Aminolipid 8 was obtained via Eschweiler-Clarke reaction from 4. Further attempts to synthetize aminolipids derivatives is in progress. LNP formulation using aminolipid 8 resulted in a particle size of 774 nm and PDI of 0.22. Although cell viability exceeded 96%, mRNA delivery was ineffective due to particle size, demanding structural modifications to optimize these nanocarriers.