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Glycans - simple or complex carbohydrates - play key roles as recognition determinants and modulators of numerous physiological and pathological processes. Thus, many biotechnological, diagnostic and therapeutic opportunities abound for molecular recognition entities that can bind glycans with high selectivity and affinity. This review begins with an overview of the current biologically and synthetically derived glycan-binding scaffolds that include antibodies, lectins, aptamers and boronic acid-based entities. It is followed by a more detailed discussion on various aspects of their generation, structure and recognition properties. It serves as the basis for highlighting recent key developments and technical challenges that must be overcome in order to fully deal with the specific recognition of a highly diverse and complex range of glycan structures.

The fabrication of a molecularly tailored surface functionalised with a saccharide binding motif, a phenyl boronic acid derivative is reported. The functionalised surface facilitated the transfer of electrons, via unique electronic interactions mediated by the presence of the boronic acid, from a macrophage cell line. This is the first example of eukaryotic cellular-electrical communication mediated by the binding of cells via their cell-surface saccharide units.

Saccharides - a versatile class of biologically important molecules - are involved in a variety of physiological and pathological processes, but their detection and quantification is challenging. Herein, surface plasmon resonance and self-assembled monolayers on gold generated from bis-boronic acid bearing a thioctic acid moiety, whose intramolecular distance between the boronic acid moieties is well defined, are shown to detect d-glucose with high selectivity, demonstrating a higher affinity than other saccharides probed, namely d-galactose, d-fructose and d-mannose.

A bis-boronic acid modified electrode for the sensitive and selective determination of glucose concentrations has been developed. The electrochemical characteristics of the sensor with added saccharides were investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The bis-boronic acid modified electrode was both sensitive and selective for glucose.