The presence of ciprofloxacin in various water sources, even at low concentrations, causes health risks and serious environmental pollution as well as development of antibiotic resistance. So, it is critically necessary to remove ciprofloxacin effectively from the effluent. Co‐doped UiO‐66 was synthesized through one‐step hydrothermal method and evaluated as an adsorbent for ciprofloxacin adsorption. Ciprofloxacin adsorption was systematically investigated revealing adsorption isotherms, kinetics, and thermodynamics. The findings revealed that Freundlich isotherm model (maximum adsorption capacity: 45.17 mg g⁻¹) at optimum experimental conditions (pH: 5, contact time: 90 min and adsorbent dosage: 0.3 g L⁻¹) and acquired data were fitted using pseudo‐second‐order kinetic model. The ciprofloxacin adsorption was determined to be a spontaneous and endothermic from thermodynamic experiments. Effects of coexisting compound in the aqueous solutions on the Co‐doped UiO‐66 adsorption performance were studied using different concentrations of NaCl solution. The ciprofloxacin removal slightly decreased in the case of increasing the concentrations of Na⁺ ions. Regeneration of the Co‐doped UiO‐66 was carried out in methanol + acetic acid solution and repeated adsorption experiments were conducted to reveal reusability of the Co‐doped UiO‐66. Its ciprofloxacin adsorption capacity reduced to 38.0 mg g⁻¹ after the four cycles indicating that the Co‐doped UiO‐66 was a reusable and potential adsorbent for ciprofloxacin adsorption process.

In recent times, many approaches have been developed against drug resistant Gram-negative bacteria. However, low-cost high effective materials which could broaden the spectrum of antibiotics are still needed. In this study, enhancement of linezolid spectrum, normally active against Gram-positive bacteria, was aimed for Gram-negative bacteria growth inhibition. For this purpose, a silica xerogel prepared from a low-cost precursor is used as a drug carrier owing to the advantages of its mesoporous structure, suitable pore and particle size and ultralow density. The silica xerogel is loaded with linezolid and capped with ε-poly-l-lysine. The developed nano-formulation shows a marked antibacterial activity against to Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. In comparison to free linezolid and ε-poly-l-lysine, the material demonstrates a synergistic effect on killing for the three tested bacteria. The results show that silica xerogels can be used as a potential drug carrier and activity enhancer. This strategy could provide the improvement of antibacterial activity spectrum of antibacterial agents like linezolid and could represent a powerful alternative to overcome antibiotic resistance in a near future.