2 value (0.989) and adjusted R

2 (0.984). The numerical optimization suggested optimal process conditions at CIP concentration of 55 mg/L, an adsorbent mass of 0.72 g/L, pH of 5.8, and a temperature of 47°C, achieving a maximum adsorption efficiency of 98.4% in 88 min. The model, supported by an F value of 345.2, exhibited robust predictive capability, offering valuable insights for process scale-up. Findings from equilibrium experiments suggested that the PSO kinetics and Langmuir isotherm displayed the highest conformity, supported by a lower error coefficient and significant regression coefficient. Additionally, the thermodynamic parameters pointed towards the spontaneous and endothermic nature of the experimental process.

The identification of pharmaceutical compounds in water sources is posing a substantial environmental challenge . The treatment of bacterial diseases in humans, livestock, and fish heavily relies on the widespread use of antibiotics . Globally, an estimated 100,000 to 200,000 tons of antibiotics are annually administered for treating human diseases . The use of antibiotics has increased significantly during the coronavirus disease, so that the use of some antibiotics reported to have increased up to sixfold . Belonging to the second generation of fluoroquinolones, Ciprofloxacin (CIP) is classified as a broad-spectrum antibiotic. The widespread use and improper disposal of antibiotics have had detrimental effects on water bodies, causing unregulated effluent discharge into waste streams, whether in their original form or as metabolites. Recent findings reveal the presence of CIP in aquatic environments worldwide, associated with a variety of adverse symptoms such as diarrhea, headaches, vomiting, and tremors. Therefore, the high persistence and potential adverse effects of CIP on aquatic organisms and human health make its removal from aqueous solutions crucial .

Numerous techniques have been investigated for eliminating CIP from water, such as adsorption, advanced oxidation processes, membrane filtration, and biological treatment. Adsorption has been given considerable consideration among these approaches owing to its cost-effectiveness and simplicity in implementation . The mechanism of adsorption includes the attachment of pollutants onto a solid substance designated as an adsorbent. Various adsorbents have been investigated for eliminating CIP, including activated carbon, zeolites, and polymers. These materials possess high surface areas and specific surface functionalities that enable effective adsorption of the target compound.

In recent years, there has been a focus on developing environmentally friendly and efficient adsorbents to remove pharmaceutical compounds from water. One such material is the CPZ nanocomposite. The CPZ nanocomposite is a unique combination of chitosan, polyacrylamide, and zeolitic imidazolate framework-8. Chitosan, a biopolymer derived from chitin, offers excellent adsorption properties thanks to its extensive surface area and diverse functional groups. Polyacrylamide enhances the mechanical stability and dispersibility of the nanocomposite, while zeolitic imidazolate framework-8 provides additional adsorption sites and selectivity towards specific pollutants.

Chitosan (CS) was selected due to its abundant amino and hydroxyl groups, which provide active sites for metal coordination and hydrogen bonding interactions with fluoroquinolone antibiotics. Polyacrylamide (PAM) offers high hydrophilicity, mechanical stability, and additional amide functionalities that enhance the structural integrity of the composite . ZIF-8, a zinc-based metal–organic framework, was introduced for its high porosity, tunable pore size, and ability to adsorb organic micropollutants through π–π stacking and electrostatic interactions. The integration of these three components is expected to create synergistic effects: (i) CS provides a biocompatible backbone with functional groups for ZIF-8 anchoring; (ii) PAM improves hydrogel stability and prevents particle aggregation, and (iii) ZIF-8 contributes high surface area and selective adsorption sites. Together, this hybrid architecture combines the flexibility and stability of polymer matrices with the high adsorption capacity of MOFs, thereby enhancing ciprofloxacin removal efficiency beyond the contribution of each component alone.

This study contributes to the advancement of knowledge by introducing an eco-friendly hybrid nanocomposite (CPZ) as a promising adsorbent for the removal of CIP from aqueous solutions. Unlike conventional adsorbents such as activated carbon or clays, the developed material combines the advantages of natural biopolymers, synthetic polymers, and metal–organic frameworks, offering a unique structural synergy. In addition to material development, the study applies a systematic experimental design approach to optimize adsorption conditions, providing methodological insights for process improvement and potential scale-up. These aspects collectively highlight the novelty of the work and position it within the growing body of research focused on sustainable strategies for mitigating antibiotic pollution in water systems.

Unlike post-impregnation or bulk-crystallization/physical-blending approaches, the proposed route is designed to promote on-matrix ZIF-8 nucleation. A CS–g–PAM network is first generated by persulfate-initiated polymerization in dilute acetic acid, providing coordinated–NH₂/–OH sites. Following a short ultrasound pulse, Zn(NO₃)₂ is introduced and allowed to complex with the backbone before the addition of 2-methylimidazole, thereby triggering heterogeneous nucleation directly on the polymer. Two brief ultrasound treatments (10–15 min each) enhance dispersion and restrict secondary growth. The fully aqueous, low-temperature protocol eliminates the need for organic solvents and solvothermal conditions. This sequence facilitates the formation of anchored MOF domains with improved textural properties compared to conventional blending methods.

Overall, present research aims to create an eco-friendly and effective adsorbent to abolish CIP from water. For this, optimizing the adsorption process by utilizing experimental design methodology is also considered. The study involves synthesizing the CPZ nanocomposite and characterizing its physicochemical properties. The adsorption experiments will be conducted using different concentrations of CIP, pH levels, temperature, adsorbent mass, and contact times. The adsorption capacity and efficiency will be evaluated using analytical techniques. Findings from this study will aid in the comprehension of the adsorption behavior of ciprofloxacin on the CPZ nanocomposite. It will also provide valuable insights into optimizing the adsorption process using experimental design methodology.