Abstract

In this study, we developed a hydrophilic interaction liquid chromatography (HILIC) stationary phase that was co-modified with polyethyleneimine-carbon quantum dots (PEI/COOH-CD). Carboxyl-functionalized carbon quantum dots were synthesized via low-temperature calcination using citric acid as the sole carbon source. This reaction employs a one-pot method to coat the modifier directly onto acid-treated silica gel; the reaction is completed within six hours, thereby eliminating the need for prior silanization. The stationary phase exhibits uniform surface fluorescence. Characterizations via elemental analysis and BET specific surface area analysis confirm that both PEI and CDs are simultaneously coated on the outer surface and embedded within the mesopores. Chromatographic performance evaluation shows that the PEI/COOH-CD@Sil column achieves baseline separation of seven major classes of polar compounds: nucleosides/bases, sulphonamides, antibiotics, alkaloids, flavonoids, amino acids, and sugars. Notably, the column efficiency for Sulfaguanidine reached 84,686 theoretical plates per meter, with an average column efficiency of 49,789 plates per meter, significantly outperforming commercial NH2-functionalized columns, bare silica gel columns, and single PEI-modified columns. This strategy employs inexpensive raw materials and a straightforward, environmentally friendly process, providing a novel universal platform for high-throughput, highly selective, and highly reproducible HILIC analysis of polar small molecules. It also possesses direct potential for commercial scale-up.

Keywords Plus: REVERSIBILITY，ISOCYANATE，ELASTOMERS，BONDS

Published in JOURNAL OF CHROMATOGRAPHY A，Volume1766；10.1016/j.chroma.2025.466609，JAN 11 2026