Encapsula Immunosome-NTA(Ni) (Non-PEGylated)

During the past five decades, various types of chemistries have been used for conjugation of molecules such as antibodies, peptides, proteins or other reactive ligands to the surface of liposomes. In general, the conjugation can be achieved through the N-terminus, the C-terminus or the available sulfur (e.g. Fab’ fraction or thiolated antibodies). Not all chemistries have the same yield and efficiency of conjugation and often reproducing biocompatible batches can be a challenge. It is well established that electron-rich ligands such as histidine, tryptophan or cysteine show a relatively high affinity to bond with electropositive transition metals, including Co+2, Ni+2, Cu+2 and Zn+2. This observation has been exploited to improve and control the association of diverse histidine-tagged peptides to liposomes containing metal-chelating lipids. Therefore, immunoliposomes can be generated using nickel-chelating lipids such as Ni-nitrilotriacetic acid (NTA) and 1,2-dioleoyl-sn-glucero-3-[N-(amino-1-carboxypentyl)-iminodiacetic acid) succinyl] (DOGS-NTA aka DGS-NTA), which are commercially available, and His-tagged proteins or peptides. When the liposomes with Ni-NTA headgroups are combined with the His residues, typically at the N- or C-terminus of proteins, the proteins reversibly anchor to the liposomes.