Preparation of a Boronate‐Functionalized Affinity Silica Hybrid Monolith Column for the Specific Capture of Nucleosides

Abstract

AbstractIn this study, a boronate affinity silica hybrid monolith was prepared for specific capture of nucleosides at physiological condition. An amino‐functionalized monolith was first synthesized via one‐step procedure in an empty HPLC column, then the fluorophenylboronic acid ligand was covalently immobilized on the amino‐functionalized hybrid monolith via in‐column reduction by sodium cyanoborohydride to form a boronate affinity silica hybrid monolith at room temperature (nearly 25°C). The mechanical stability and permeability of the boronate affinity hybrid monolith were characterized using scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FT‐IR). The boronate affinity silica hybrid monolith exhibited excellent specificity toward nucleosides and could bind with cis‐diol containing compounds at low pH (6.5). The binding capacity of the monolith for adenosine was nearly 693 μg/mL even at pH 6.5. Furthermore, the boronate affinity monolith was applied to the separation of nucleosides from urine sample at physiological condition. The obtained result revealed that the monolith could enrich nucleosides effectively with a good repeatability. The recovery values for the four nucleosides spiked at the concentration of 4 μg/mL were observed in the range of 76.58 ‐ 83.01%, and the RSDs were < 7.65%, respectively.