Fig. 2: Synthesis and screening of AA-lipidoids for targeted RNA delivery to activated fibroblasts.

a One-pot, two-step modular synthesis of AA-lipidoids. A representative synthesis of AA-T3A-C12 is shown. Anisoyl-NHS, polyamines, and epoxides were used to build a combinatorial library of 18 AA-lipidoids. b First-round screening of lipidoids and AA-lipidoids with high potency (n = 3/group). Lipidoids without anisamide were synthesized by the traditional ring-opening reactions between epoxides and polyamines. GFP siRNA-loaded LNPs were formulated to treat activated 3T3-GFP fibroblasts for 48 h to obtain their knockdown efficiency. The dashed line indicates 80% GFP knockdown. c Statistical analysis of structure–activity relationships. GFP knockdown efficiency was plotted based on lipidoids with or without anisamide. d Second round screening of lipidoids and AA-lipidoids with high dependency on sigma receptor-mediated transfection (n = 3/group). Activated 3T3-GFP fibroblasts were pre-treated with haloperidol (HP) to block sigma receptors before treatment with GFP siRNA-loaded LNPs. e Statistical analysis of the relationship between sigma receptor blocking and knockdown efficiency. GFP knockdown efficiency was plotted based on treatment with or without HP. Data are presented as mean ± SD. ns not significant; *p < 0.05, **p < 0.01. c–e two-sided t-test. Source data are provided as a Source Data file.