Hybrid magnetic GO·CNT·Fe3O4 nanomaterial for escitalopram removal: Synthesis, characterization, adsorption mechanisms, and biosafety assessment

The widespread occurrence of pharmaceutical residues like the antidepressant escitalopram (ESC) in wastewater has raised growing environmental and public-health concerns. Conventional treatment technologies remain largely ineffective at low contaminant concentrations and rarely account for post-adsorption toxicological safety, creating a critical gap in sustainable water remediation strategies. To address this, a hybrid magnetic carbon nanomaterial containing graphene oxide carbon nanotubes and magnetic nanoparticles (GO·CNT·Fe 3 O 4 ) was developed that enhances adsorption efficiency, enables magnetic recovery, and improves life-cycle safety assessment. The nanocomposite was synthesized via a one-step co-precipitation method and thoroughly characterized using SEM/EDS, HR-TEM, XPS, Raman, XRD, FTIR, VSM, TGA, and zeta-potential analyses. Batch adsorption experiments investigated pH, dosage, initial ESC concentration, coexisting ions, isotherms, kinetics, and thermodynamics, alongside in vitro cytotoxicity and phytotoxicity assays. The optimized GO·CNT·Fe 3 O 4 (2:1:1) formulation achieved 98% ESC removal and a maximum capacity of 150 mg g -1 , with adsorption governed by the Elovich kinetic model and the Sips isotherm, indicating heterogeneous chemisorption in an exothermic and spontaneous process. The material-maintained performance over five regeneration cycles and exhibited minimal cytotoxicity and phytotoxicity after adsorption, unlike the free drug. Overall, this study introduces a highly efficient, reusable, and biologically safe magnetic nanoadsorbent, offering a sustainable platform for antidepressant (and other drug or pollutant) removal and an advanced life-cycle-oriented nanotechnology for water remediation.