Browsing by Author "Ahmed H. Nadim"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Eco-friendly tea waste magnetite nanoparticles for enhanced adsorptive removal of norfloxacin and paroxetine from water
    (Elsevier Inc., 2024-11-01) Lamis M. Fahmy; Dalia Mohamed; Marianne Nebsen; Ahmed H. Nadim
    Traces of pharmaceuticals have been detected in water cycle raising concerns regarding the potential risks to human health and aquatic environment. Accordingly, removal of such compounds from water samples is a major concern. Herein, a facile and green NaOH modified tea waste magnetite nanoparticles have been fabricated for the adsorptive removal of a commonly used antibiotic (norfloxacin) and antidepressant (paroxetine) from water samples. The synthesized nanoparticles were characterized using TEM, FT-IR, DLS and VSM. Factors affecting the adsorption efficiency have been investigated with respect to pH (5, 7 and 9), adsorbent amount (0.125, 0.25 and 0.5 g), initial drug concentration (25, 50 and 100 µg/mL) and contact time (0.5, 1 and 2 h). The adsorption isotherms have been calculated. A percentage removal of 98 % and 99 % were obtained for simultaneous removal of 50 µg/mL norfloxacin and paroxetine, respectively in 2 h. Monitoring norfloxacin and paroxetine concentrations was performed through a validated HPLC-DAD method. The reusability of the nanoparticles has been studied for 3 adsorption–desorption cycles. No significant loss in adsorption efficiency was observed offering a sustainable water treatment. This study would offer a facile, green and economic protocol for the removal of complex organic compounds from water resources.
  • Thumbnail Image
    Item
    Enhanced LED light driven photocatalytic degradation of Cefdinir using bismuth titanate nanoparticles
    (Nature Research, 2025-07-08) Sara Ishaq; Ahmed H. Nadim; Joliana F. Farid; Sawsan M.Amer; Heba T. Elbalkiny
    Photodegradation of antibiotics using visible light represents a promising approach for efficiently removing antibiotic contaminants from water sources. This study investigated bismuth titanate (Bi4Ti3O12) nanoparticles for the photodegradation of Cefdinir (CEF), a third-generation cephalosporin, under visible LED irradiation. Bismuth titanate nanoparticles were synthesized and characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), and diffuse reflectance spectroscopy (DRS). Factors affecting the degradation protocol were optimized using a central composite design model, and the degradation efficiency was assessed using a validated RPHPLC method. Results of the experimental design demonstrated that bismuth titanate nanoparticles exhibited high photocatalytic performance (⁓ 98% photodegradation), which was found in an optimum condition of 0.05 g/L of BIT-NP in pH 5 for 50 µg/mL of CEF in 1 h at room temperature. The degradation efficiency depended on the concentration of the nanoparticles, the initial concentration of CEF, and pH. The antimicrobial effect of CEF was assessed before and after the degradation process, and the loss of antibiotic activity was observed after treatment. The findings provide valuable insights into developing innovative photocatalytic materials for the economic remediation of antibioticcontaminated water sources using eco-friendly LED sources for degradation under visible light for the first time. This would offer a promising solution to mitigate the environmental impact of antibiotic residues.