Modification of Amino-Functionalized Organic-Silica Hybrid Monoliths via a Catalyst-Free Amino-Yne Click Reaction for Capillary Liquid Chromatography

A novel post-modification strategy was developed for rapid functionalization of monoliths through amino-yne click chemistry. This approach enabled the conjugation of activated alkynes onto amino-functionalized organic-silica hybrid monolith surfaces under mild, catalyst-free conditions. Systematic investigation of critical reaction parameters was conducted to optimize the post-modification process. The morphological and structural characteristics of the prepared monolith were characterized by scanning electron microscopy (SEM) and nitrogen adsorption measurements. The successful grafting of functional groups onto the monolith surface was confirmed by contact angle analysis, Fourier transform infrared (FT-IR) spectroscopy, and x-ray photoelectron spectroscopy (XPS). The functionalized monolith demonstrated chromatographic selectivity for diverse analytes, including phenolic compounds and some weakly polar/nonpolar compounds (benzoin/benzoin methyl ether, styrene/ p -chlorostyrene, and 1-naphthylethylamine/naphthalene). Furthermore, it was successfully applied to the quantitative analysis of honokiol in authentic magnolol samples, showcasing its potential for practical analytical applications.