We report an approach integrating the synthesis of protein‐imprinted nanogels (“plastic antibodies”) with a highly sensitive assay employing templates attached to magnetic carriers. The enzymes trypsin and pepsin were immobilized on amino‐functionalized solgel‐coated magnetic nanoparticles (magNPs). Lightly crosslinked fluorescently doped polyacrylamide nanogels were subsequently produced by high‐dilution polymerization of monomers in the presence of the magNPs. The nanogels were characterised by a novel competitive fluorescence assay employing identical protein‐conjugated nanoparticles as ligands to reversibly immobilize the corresponding nanogels. Both nanogels exhibited K d <10 pM for their respective target protein and low cross‐reactivity with five reference proteins. This agrees with affinities reported for solid‐phase‐synthesized nanogels prepared using low‐surface‐area glass‐bead supports. This approach simplifies the development and production of plastic antibodies and offers direct access to a practical bioassay.

Imprinting of an ion-pair in presence of mutually compatible anion and cation host monomers leads to polymers showing enhanced ion uptake in competitive high ionic strength buffers.

2,6′- and 2,3′-sialyllactose imprinted polymers (MIPs) capable of discriminating between two modes of sialic acid linkages in glycans are reported.

Aberrant glycosylation has been proven to correlate with various diseases including cancer. An important alteration in cancer progression is an increased level of sialylation, making sialic acid one of the key constituents in tumor-specific glycans and an interesting biomarker for a diversity of cancer types. Developing molecularly imprinted polymers (MIPs) with high affinity toward sialic acids is an important task that can help in early cancer diagnosis. In this work, the glycospecific MIPs are produced using cooperative covalent/noncovalent imprinting. We report here on the fundamental investigation of this termolecular imprinting approach. This comprises studies of the relative contribution of orthogonally interacting functional monomers and their synergetic behavior and the choice of different counterions on the molecular recognition properties for the sialylated targets. Combining three functional monomers targeting different functionalities on the template led to enhanced imprinting factors (IFs) and selectivities. This apparent cooperative effect was supported by 1 H NMR and fluorescence titrations of monomers with templates or template analogs. Moreover, highlighting the role of the template counterion use of tetrabutylammonium (TBA) salt of sialic acid resulted in better imprinting than that of sodium salts supported by both in solution interaction studies and in MIP rebinding experiments. The glycospecific MIPs display high affinity for sialylated targets, with an overall low binding of other nontarget saccharides.

We report an approach integrating the synthesis of protein‐imprinted nanogels (“plastic antibodies”) with a highly sensitive assay employing templates attached to magnetic carriers. The enzymes trypsin and pepsin were immobilized on amino‐functionalized solgel‐coated magnetic nanoparticles (magNPs). Lightly crosslinked fluorescently doped polyacrylamide nanogels were subsequently produced by high‐dilution polymerization of monomers in the presence of the magNPs. The nanogels were characterised by a novel competitive fluorescence assay employing identical protein‐conjugated nanoparticles as ligands to reversibly immobilize the corresponding nanogels. Both nanogels exhibited Kd<10 pM for their respective target protein and low cross‐reactivity with five reference proteins. This agrees with affinities reported for solid‐phase‐synthesized nanogels prepared using low‐surface‐area glass‐bead supports. This approach simplifies the development and production of plastic antibodies and offers direct access to a practical bioassay.