Recent advances in zeolitic imidazolate framework-based materials for ciprofloxacin removal from aqueous environments

Abstract

CIP is a widely used fluoroquinolone antibiotic that poses increasing environmental and public health concerns due to its persistence and biological activity in aquatic environments. Zeolitic imidazolate frameworks, known for their high surface area, tunable porosity, and versatile surface chemistry, have gained significant attention as advanced adsorbents for antibiotic removal. This review critically evaluates recent developments from 2020 to 2025 regarding the use of ZIFs for CIP remediation, with particular emphasis on adsorption mechanisms and structure–performance relationships. A structured literature search was performed using Scopus, Web of Science, Google Scholar, and ScienceDirect. Of the 69 initially identified studies, 31 met the predefined inclusion criteria and were subjected to in-depth analysis. Nearly half of the reviewed investigations examined CIP concentrations below 30 mg/L, while approximately 42% reported contact times exceeding 100 min. Among studies reporting solution pH, near-neutral conditions were investigated most frequently, underscoring the influence of pH on CIP-removal behavior. Among the studied materials, ZIF-8 and ZIF-67 were the most extensively investigated. Several ZIF-based composites, including Fe–ZIF-8, ZIF-8/SC hydrogel beads, and ZIF-8/SOD hybrids, achieved near-complete CIP removal, demonstrating enhanced adsorption performance. The adsorption processes most frequently followed the Langmuir isotherm and pseudo-second-order kinetic models, involving π–π interactions, electrostatic attraction, hydrogen bonding, and metal–ligand coordination. Among the studies reporting thermodynamic parameters, endothermic adsorption predominated, with improved removal generally observed at elevated temperatures. Overall, this review establishes clear connections between ZIF structural features and CIP adsorption efficiency, elucidates pH-dependent mechanisms, and synthesizes recent experimental and modeling approaches, providing practical guidance for the rational design of next-generation ZIF-based adsorbents.