This research investigated the photocatalytic degradation of ciprofloxacin by titanium dioxide nanoparticles immobilized on a glass plate in an aqueous solution. The important point about this process is immobilization on glass plate, which resolves difficulties related to separation of catalysts from the solution in the application of sole nanoparticles as well as reusability of nanoparticles. Application of nanoparticles without immobilization on a support medium causes toxic effects in aqueous solutions, which was fixed through immobilization on a glass plate in this study. In this research, 1 gL⁻¹ of TiO₂ was immobilized on a glass plate. XRD and SEM indicated that the TiO₂ immobilized on the glass plate was highly pure and uniform in size (39.2–74.9 nm). The maximum ciprofloxacin removal efficiency from the synthetic aqueous solution was obtained at the optimal pH of 5, contact time of 105 min, and ciprofloxacin initial concentration of 3 mgL⁻¹. The extent of ciprofloxacin removed under optimal conditions was obtained as 92.81% and 86.57% from the synthetic and real samples, respectively. Evaluation of linear models of kinetics and adsorption isotherms indicated that the data followed pseudo-first-order kinetics as well as Langmuir–Hinshelwood and Freundlich isotherms. Thermodynamic studies revealed that the adsorption of ciprofloxacin on TiO₂ nanoparticles immobilized on glass plate is an endothermic and physical process. Considering the high efficiency of this process under real conditions, it can be used for the removal of resistant pollutants from industrial wastewater.

Ciprofloxacin is used in the treatment of bacterial infections. Because ciprofloxacin is not effectively degraded by biological processes, advanced oxidation processes such as photocatalytic ozonation are applied to remove this antibiotic from wastewater. The aim of this study was to investigate photocatalytic ozonation for the removal of ciprofloxacin from aquatic environments and optimization of the effective parameters of the process. For this purpose, ZnO nanoparticles were synthesized using the thermal method and immobilized on the surface of stones. The structural properties of the nanoparticles were determined by XRD, TEM, Photoluminescence (PL) and SEM. Experiments were carried out in a Plexiglas reactor supported with the continuous injection of ozone. The effective parameters for removal efficiency were reaction time, initial concentration of ciprofloxacin, pH, photocatalyst concentration and reaction kinetics. The highest ciprofloxacin removal efficiency occurred at the following optimal conditions: pH of 7, reaction time of 30 min, photocatalyst concentration of 3 g/L and initial ciprofloxacin concentration of 10 mg/L. Removal efficiency of 96% was obtained under these conditions. Linear kinetic models showed that the process followed pseudo-first order and Langmuir-Hinshelwood kinetics. This process had a high removal efficiency and suitable for removal of ciprofloxacin from aquatic environments.GRAPHICAL ABSTRACT

ZnO nanoparticles have been synthesized via a hydrothermal technique has been utilized for synthesizing ZnO nanoparticles, which had been immobilized on glass plates for the purpose of settling the portion of p-nitroaniline (PNA) removal that can be attained by performing a photocatalytic degradation process (UV/ZnO). In order to evaluate the structural properties of nanoparticles, we have exerted the SEM, TEM, PL, DRS, and XRD analyzes. The highest efficiency for elimination of p-nitroaniline (94/4%) was achieved via the utilization of a photocatalytic degradation procedure (UV/ZnO) at the optimal pH of 7, 105 min contact time, at concentration of p-nitroaniline 10 mg/L, with an immobilized dose of 1 g/L for ZnO. The total organic carbon (TOC) removal has been ascertained under the optimal conditions (maximum 72.2%). Thus, the photocatalytic degradation procedure (UV/ZnO) is apparently a viable proposal for degrading the organic compounds from aqueous solution.

Background: Antibiotics such as ciprofloxacin (CIP) are even more important in bacterial resistance, even at low concentrations. The aim of this research was to synthesize CuFe2 O4 @methylcellulose (MC) as a new nano-photocatalyst for degradation of CIP from aqueous solution. Methods: The nano-photocatalyst (CuFe2 O4 @MC) was characterized by FESEM, energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), and vibrating sample magnetometer (VSM). Powder XRD and EDS analysis confirmed the formation of pure-phase spinel ferrites. After CuFe2 O4 @MC characterization, the effective parameters in removal efficiency of CIP such as reaction time, initial antibiotic concentration, pH, photocatalyst loading, and degradation kinetic were investigated and conditions were optimized. Then, CIP degradation experiments were conducted on the real sample in the optimal conditions. The removal of chemical oxygen demand (COD) was determined under optimum conditions. Results: The structural characterization of the magnetic nanobiocomposite showed that it is in nanoscale, ferromagnetic property, and thermal stability. The optimal conditions were obtained at pH = 7, irradiation time (90 minutes), photocatalyst loading (0.2 g), and initial concentration of CIP (3 mg/L). The removal efficiency of CIP in the optimal conditions was obtained as 80.74% and 72.87% from the synthetic and real samples, respectively. The removal of COD was obtained as 68.26% in this process. The evaluation of kinetic linear models showed that the photocatalytic degradation process was fitted by pseudo-first order kinetic model and Langmuir-Hinshelwood. CuFe2 O4 @MC photocatalyst had a good stability and reusability for the fourth runs. Conclusion: The photocatalytic degradation of CIP from aqueous media with CuFe2 O4 @MC photocatalyst has a high efficiency, which can be used in the treatment of pharmaceutical wastewaters.

Background: The presence of antibiotics such as metronidazole in wastewater even at low concentrations requires searching for a suitable process such as advanced oxidation process (AOP) to reduce the level of pollutants to a standard level in water. Methods: In this study, zinc oxide (ZnO) nanoparticles were synthesized by thermal method using zinc sulfate (ZnSO4 ) as a precursor, then, stabilized on stone and was used as a catalyst, in order to degrade metronidazole by photocalytic process. Effective factors on the removal efficiency of metronidazole including the initial metronidazole concentration, contact time, pH, and 0.9 gL-1 ZnO stabilized on the stone surface were investigated. Results: The X-ray diffraction (XRD) studies showed that the synthesized nanomaterials have hexagonal Wurtzite structure. Also, scanning electron microscopy (SEM) analysis revealed that the average crystalline size of the synthesized ZnO particles was in the range of 1.9-3.2 nm. The spectra represented a sharp absorption edge at 390 nm for ZnO nanoparticles corresponding to band gap of 3.168 eV. The BET-BJH specific surface area of the synthesized ZnO nanoparticles was 25.504 m2 /g. The EDS spectrum of ZnO nanoparticles showed four peaks, which were identified as Zn and O. The maximum removal efficiency was 98.36% for the synthetic solution under a specific condition (pH = 11, reaction time = 90 minutes, ZnO concentration = 0.9 gL-1, and the initial concentration of metronidazole = 10 mgL-1). The photocatalytic degradation was found to follow pseudo-first-order degradation kinetics. Conclusion: Therefore, the ZnO nanoparticles synthesized by thermal decomposition are suitable and effective photocatalytic materials for degradation of pharmaceutical contaminants.

Nanoparticles are known to have a distinctive interaction at the molecular level with biological systems and widely used in cancer treatment. Silver nanoparticles (AgNPs) was characterized by UV-visible, XRD and TEM. The phytochemical screening was performed to study the plant chemical compounds. The cytotoxic properties of AgNPs on breast cancer cells (MCF-7 line) have obtained using MTT assay. The potent inhibitory effects of nanoparticles on Cyclin-D1 gene expression were demonstrated by western blotting. The AgNPs (7-10 nm) were synthesized using Tamarix hispida. The phytochemical analysis showed that T. hispida is rich in proteins, carbohydrates, and alkaloids. The western blot analysis showed that the AgNPs inhibits the Cyclin D1 expression and decreases cell proliferation. In conclusion, the results provide a promising approach for designing a new AgNPs-mediated drug delivery study due to the remarkable exhibition of cytotoxicity activity for cancer therapy.