ILT is a group of lipid-coated water soluble iron oxide nanoparticles that are covalently modified with strong metal-chelating nitrilotriacetic acid (NTA) groups and pre-charged with nickel. Their zeta potential ranges from -10 mV to -30 mV. The overall thickness of the organic layers is about 1-2 nm. The hydrodynamic size that is established using a Zeta Trac (DLS) is about 3-8 nm larger than the inorganic iron oxide core size as measured with TEM.
ILTs have a high affinity to proteins with histidine (His) tag, about 20-200 fold higher than non-His tagged proteins depending on the iron oxide nanoparticle core size. His-tagged proteins or other biomolecules can be easily attached to ILTs and presented in a directional manner for enhanced signal-to-noise and reproducibility. Lipid-coated nanoparticles have excellent compatibility for in vivo studies because these are prepared with physiological lipids. ILTs are quite stable in most common buffers, such as borate, Tris, HEPES, PBS and MES buffers, as well as in cell culture medium.