Dual-responsive N-isopropylacrylamide and boron affinity nanoparticles for application to selective recognition of glycoproteins.

This research examines the utilization of dendritic fibrous nanosilica (DFNS) as a matrix for the introduction of 3-carboxyphenylboronic acid (CPBA) and N-isopropylacrylamide (NIPAM) in the preparation of a boron-affinity material (DFNS@BN) exhibiting dual pH- and thermo-responsive behavior. DFNS mesopores, featuring a folded surface and centrally divergent pores, were synthesized through a one step hydrothermal approach. More importantly, synergistic coupling between pH-controlled boronate covalent recognition and temperature-tunable hydrogen-bond conformational regulation of thermoresponsive polymers is realized. At temperatures below the lower critical solution temperature (LCST, 32 °C) under weakly alkaline conditions (pH > 7), dual intermolecular forces jointly boost glycoprotein adsorption capacity; at temperatures above 32 °C under acidic environments, simultaneous dual stimuli trigger thorough dissociation of captured glycoproteins. The material manifested selective adsorption of glycoproteins (transferrin, ovalbumin, and horseradish peroxidase) via the dual response of boron affinity and thermo-responsiveness. The adsorption kinetics adhered to the proposed secondary adsorption model, and the Langmuir isothermal adsorption model was employed. In the analysis of real samples, the material successfully enriched nine glycoproteins from human saliva samples. These findings imply the potential of boron-affinity materials in glycoprotein separation and enrichment, offering a promising strategy for the development of effective glycoprotein separation agents for bioanalytical applications.