Bio-inspired chitosan/polydopamine-nanoparticle based sorbent bead: A versatile platform for separation and HPLC analysis of tetracycline antibiotics from various sample matrix

Emmanuvel Arputharaj^a, Yu-Hui Huang^a, Shivangi Singh^a, Chen-Han Zhuang^a, Kuei-Ying Lin^b, Sri Sudewi^c, You-Rong Wu^a, Yeou-Lih Huang*^a,d,e,f,g

^a Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung, Taiwan

^b Department of Laboratory Medicine, Municipal Ta-Tung Hospital, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan

^c Department of Pharmacy, Faculty of Mathematics and Natural Science, Universitas Sam Ratulangi, Manado, Indonesia

^d Research Center for Precision Environmental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan

^e Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan

^f College of Professional Studies, National Pingtung University of Science and Technology, Pingtung, Taiwan

^g Department of Chemistry, National Sun Yat-Sen University, Kaohsiung, Taiwan

This study introduces an innovative bio-based sorbent bead crafted by integrating chitosan (CS) biopolymers, Fe(NO₃)₃ and polydopamine nanoparticles (PDA NPs) via glutaraldehyde crosslinking. The primary focus of this study was the concurrent separation of diverse tetracycline antibiotics (TCs), followed by rigorous reversed-phase liquid chromatography analysis. The fabricated CS/Fe@PDA sorbent beads were comprehensively characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy, revealing a surface rich in active carbon (C), nitrogen (N), and oxygen (O) moieties. The proposed method demonstrated substantial analytical robustness, enabling the sorbent bead to detect low concentrations of TCs, with limit of detection values ranging from 142 to 303 µg L⁻¹. Notably, the established linear range of 450–2000 µg L⁻¹ extended the applicability of this approach to food and pharmaceutical product analysis. This study anticipated a paradigm shift in sample pre-treatment methodologies for TC analysis and envisions CS/Fe@PDA beads as a valuable tool for further advancements in separation science. The proposed bio-sorbent introduced a promising avenue for optimizing TC analysis, contributing to broader goals of food safety and pharmaceutical quality assurance. The results and insights from this study are expected to provide valuable inputs for ongoing efforts of the Food and Drug Administration to enhance analytical methodologies for food and drug safety.