title: Covalent attachment of insulin to the outer surface of liposomes.
abstract: We describe a method for covalent binding of insulin to the outer surface of multilamellar liposomes loaded with spin label. Encapsulation of the label Tempocholine-nitroxide within the aqueous phases of liposomes is controlled by Electron Spin Resonance. The binding of insulin is performed using the Carlsson's heterobifunctional reagent: N-succinimidyl 3-(2-pyridyldithio) propionate. The coupling method results in efficient attachment of 2. 64.10(-4) mole of insulin per mole of phospholipid; the integrity of these vesicles is not modified as confirmed by spin resonance analysis. Moreover, the liposome-coupled insulin retains its antigenic specificity as shown by radioimmunoassays.
mesh_terms: D000818:Animals; D002417:Cattle; D003497:Cyclic N-Oxides; D004578:Electron Spin Resonance Spectroscopy; D000939:Epitopes / Q000032:analysis; D007328:Insulin / Q000276:immunology / Q000378:metabolism*; D008081:Liposomes / Q000378:metabolism*; D008722:Methods; D009609:Nitrous Oxide; D011863:Radioimmunoassay; D013113:Spin Labels
chemical_list: D003497:Cyclic N-Oxides; D000939:Epitopes; D007328:Insulin; D008081:Liposomes; D013113:Spin Labels; C017743:tempocholine; D009609:Nitrous Oxide