The sterol models were simulated in DSPC bilayers and compared with cholesterol, ensuring a correct trend in terms of packing, insertion, and melting temperature relative to the experimental data. See Figure -24 in the supporting information for the bonded distributions along with these properties mentioned above. In addition to sterols, we have also included PEGylated lipid models in the Martini 3 LNP toolbox. Leveraging the versatility of Polyply, adjustable PEG head lengths are available, which could be combined with the Martini 3 tail library and with fragments exclusively generated to facilitate the modeling of DMG-PEG and ALC-0159. As an example, we provide a model of DMG-PEG 2000 and ALC-0159. It is important to note, however, that the use of PEG in Martini 3 currently requires some adjustments in the interactions between SN3r and charged (Q) beads .