Orientationally Fabricated Zwitterionic Molecularly Imprinted Nanocavities for Highly Sensitive Glycoprotein Recognition

Abstract

Glycoprotein recognition has recently gained a lot of attention, since glycoproteins play important roles in a diverse range of biological processes. Robustly synthesized glycoprotein receptors, such as molecularly imprinted polymers (MIPs), which can be easily and sustainably handled, are highly attractive as antibody substitutes because of the difficulty in obtaining high-affinity antibodies specific for carbohydrate-containing antigens. Herein, molecularly imprinted nanocavities for glycoproteins have been fabricated via a bottom-up molecular imprinting approach using surface-initiated atom transfer radical polymerization (SI-ATRP). As a model glycoprotein, ovalbumin was immobilized in a specific orientation onto a surface plasmon resonance sensor chip by forming a conventional cyclic diester between boronic acid and cis-diol. Biocompatible polymer matrices were formed around the template molecule, ovalbumin, using SI-ATRP via a hydrophilic comonomer, 2-methacryloyloxyethyl phosphorylcholine, in the presence of pyrrolidyl acrylate (PyA), a functional monomer capable of electrostatically interacting with ovalbumin. The removal of ovalbumin left MIPs with binding cavities containing boronic acid and PyA residues located at suitable positions for specifically binding ovalbumin. Careful analysis revealed that strict control over the polymer significantly improved sensitivity and selectivity for ovalbumin recognition, with a limit of detection of 6.41 ng/mL. Successful detection of ovalbumin in an egg white matrix was demonstrated to confirm the practical utility of this approach. Thus, this strategy of using a polymer-based recognition of a glycoprotein through molecularly imprinted nanocavities precisely prepared using a bottom-up approach provides a potentially powerful approach for detection of other glycoproteins.

Molecular Imprinted Polymers Coupled to Photonic Structures in Biosensors: The State of Art

“…Moreover, atom transfer radical polymerization (ATPR) was also exploited for the preparation of MIPs on the SPR platforms: MIP nanocavities for glycoproteins were fabricated via a bottom-up molecular imprinting approach using surface-initiated ATPR and the model glycoprotein ovalbumin, which was immobilized in a specific orientation onto an SPR chip by forming a conventional cyclic diester between the glycomoiety and a boronic acid and cis diol. The sensor reported selectivity for ovalbumin recognition, with an LoD of 6.41 ng/mL [ 65 ]. Hence, the reported sensors performances account for the effectiveness of strategies aimed at a fine control of the MIP polymerization.…”

Site-specific post-imprinting modification of molecularly imprinted polymer nanocavities with a modifiable functional monomer for prostate cancer biomarker recognition

“…These results suggest that the MIPs prepared with 2-and 3-h polymerizations may be too thick to effectively remove the template PSA, which has a size of approximately 4 nm. Thus, an appropriate polymer thickness relative to the size of the target protein is critical in molecular imprinting with an immobilized template and subsequent PIM based on capping treatment [42][43][44].…”

Towards Detection of Glycoproteins Using Molecularly Imprinted Nanoparticles and Boronic Acid-Modified Fluorescent Probe

“…Molecularly imprinted polymers (MIPs) have significant advantages in terms of stability and reusability [12]. In the literature, several MIPs have been described to bind glycoproteins via selective boronic acid–glycan interactions [13,14,15,16,17,18]. Because the formation of a covalent bond between boronic acid and the cis –diol structure in the carbohydrate moiety of glycosylated proteins can be accomplished in an aqueous solution, MIPs designed for glycoprotein recognition are often prepared from boronic acid-based building blocks.…”