**Imidazole cholesterol ester (ICE)** is a sterol‑based ionizable cationic lipid invented by Translate‑Bio (WO2018/089790 A1) for mRNA‑loaded lipid‑nanoparticle (LNP) pulmonary delivery. It fuses an imidazole pH‑responsive headgroup with cholesterol via ester linkage. Typically formulated as a three‑component LNP (ICE : DOPE : DMG‑PEG2K = 60 : 35 : 5 mol ratio), ICE‑LNPs achieve high mRNA encapsulation (>80‑90 %), good nebulization stability and low toxicity. Upon cellular uptake, imidazole mediates endosomal escape; the ester bond degrades to yield cholesterol, conferring favorable biocompatibility. Animal studies demonstrate robust CFTR protein expression in bronchial and alveolar lung tissue after inhalation, making ICE promising for cystic‑fibrosis mRNA therapy.

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.