Molecular imprinting resonant light scattering sensor based on teamed boronate affinity for highly specific detection of glycoprotein

It is challenging to detect and enrich glycoproteins in complex biological samples because they are low in natural abundance, highly flexible in conformation and there are many interfering substances in the samples. To overcome these challenges, magnetic Fe3O4 nanoparticles (NPs) were prepared, in which the surface was modified by metal-organic frameworks (MOFs) and then by molecularly imprinted polymers (MIPs). Combined with the teamed boronate affinity (TBA) strategy, the selectivity and sensitivity detection of glycoprotein ovalbumin (OVA) were realized. The magnetic Fe3O4 NPs were coated with MOFs to facilitate the adsorption of AuNPs, onto which the TBA moieties composed of 2-mercaptoethylamine and 4-mercaptophenylboronic acid were pre-assembled. The final magnetic Fe3O4@TBA/MIPs NPs featured shallow imprinted cavities, resulting in rapid mass transfer of the target glycoprotein (equilibrium time 20 min). In particular, the TBA strategy relied on N-B synergy, resulting in high specificity (IF = 4.52) and high sensitivity (limit of detection 13 pM) for the detection of OVA at physiological pH (7.4). This strategy provides an extremely convenient method for detecting and quantifying low-abundance glycoprotein in complex biological samples, without destroying the structure and function of the target glycoprotein.