Modification of carboxymethylcellulose materials for use in the treatment of aquaculture water for fluoroquinolone antimicrobials

Overuse of fluoroquinolone antimicrobials (FQs) in agriculture is harmful to human health and can cause damage to aquatic environments. To address this issue, the development of environmentally friendly materials that are capable of adsorbing FQ residues is essential. In this study, a carboxymethyl cellulose–polyvinyl alcohol–citric acid (CMC–PVA–CA) composite incorporating magnesium cations (CMC–PVA–CA–Mg) was used to enhance the selective FQ adsorption capacity. The characteristics of the composite material were investigated using physical–chemical techniques. Adsorption kinetic and equilibrium isotherm models (the Langmuir and Freundlich models) were employed to gain insight into the underlying adsorption mechanisms of this material, and the capacity of the material to adsorb FQs was evaluated and compared with that of commercial solid-phase extraction (SPE) adsorbents. High-performance liquid chromatography with a fluorescence detector (HPLC–FLD) was then used to detect FQs in aquaculture water. The composite material was able to recover more than 70% of the FQs with a low standard deviation of less than 2%. • A CMC–PVA–CA–Mg composite was developed for selective adsorption of FQ residues. • Adsorption mechanisms were analyzed using Langmuir and Freundlich isotherm models. • The composite outperformed commercial SPE adsorbents in FQ recovery efficiency. • HPLC–FLD analysis showed >70% FQ recovery with a low standard deviation (<2%).