Molecular Imprinted Silica with West Nile Antibody Templates show Specific and Selective Binding in Immunoassays

Abstract

A new molecular imprinting technique was developed for molecularly imprinted polymer particles (MIPs). Particles were synthesized using organic silane chemistries by a sol-gel process, where the relative amount of active monomers was complementary matched to the relative amount of surface charges of the West Nile antibody template. Synthesized MIPs showed specific binding to affinity purified polyclonal West Nile antibodies (WNA) with a loading capacity of 80 µg/mg, while MIPs absorbed non-specific proteins at a loading capacity of 28 µg/mg. A dissociation constant of Kd=57.45 μM was measured from the binding isotherms. MIPs selectively absorbed 27 times more WNA than either albumin or immunoglobulin, while MIPs absorbed 16 times more WNA than nonimprinted particles (NIPs). Finally, fluorescently labeled MIPs were incubated in a high bind 96 well plate previously loaded with template, albumin, or immunoglobulin as an immunoassay test. Fluorescent MIPs significantly bound more to wells with WNA than any other control. Thus, the development of new affordable and robust immunoassays with MIPs would be possible in the future.