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Omeprazole, a proton pump inhibitor, is used for gastric and duodenal ulcers, gastroesophageal reflux disease, Helicobacter pylori infection, etc. Current research is based on the loading of omeprazole on surface silver nanoparticles by chemical method. The appearance of an absorption peak at 421 nm confirmed the synthesis of nanoparticles. The FT-IR further confirmed the conjugation of functional groups present in omeprazole moiety with silver. The size and morphology were elucidated by transmission electron microscopy and X-ray diffraction which revealed a spherical shape with an average particle size of 16–20 nm. To know enhancement in their efficacy, the omeprazole-loaded nanoparticles were evaluated against antibacterial, urease inhibition, and antioxidant activities. Nanoparticles showed significant antibacterial potential against Staphylococcus aureus and Escherichia coli with 12 ± 0.41 and 13.6 ± 1.02 mm zones of inhibition, respectively. Almost 2.43 times enhanced urease inhibitory activity was found for nanoparticles (IC50 = 2.17 ± 0.10 µg·mL−1) as compared to omeprazole (IC50 = 5.28 ± 0.14 µg·mL−1). The radical scavenging activity of nanoparticles also increased significantly. The synthesized nanoparticles were docked in the active site of urease to investigate their binding mode. Due to excellent urease and bacterial inhibition, these nanoparticles can be used for ulcers.

Dry reforming of methane (DRM) which also known as CO2 reforming of methane is a well-investigated reaction to serve as an alternative technique to attenuate the abundance of greenhouse gases (CO2 and CH4). The syngas yielded is the main component for the liquid fuels and chemicals production in parallel with the fluctuating price of oil. Major researches were executed to seek for the well-suited catalysts before the commercialization of DRM can be realized. However, severe deactivation due to the carbon formation restricted the usage of promising Ni-based catalysts for DRM. Meanwhile, the deactivation on these catalysts can be associated with the operating conditions of DRM, which subsequently promoted the secondary reactions at different operating conditions. In fact, the parametric study could provide a benchmark for better understanding of the fundamental steps embodied in the CH4 and CO2 activation as well as their conversions. This review explores on the influences of the reaction operating parameters in term of the reaction temperatures, reactant partial pressures, feed ratios, and weight hourly space velocity (WHSV) on catalytic performance and carbon accumulation for the DRM.

Graphene quantum dots (GQDs), a new solid-state electron transfer material was anchored to nitrogen-doped TiO2 via sol gel method. The introduction of GQDs effectively extended light absorption of TiO2 from UV to visible region. GQD-N-TiO2 demonstrated lower PL intensity at excitation wavelengths of 320 to 450 nm confirming enhanced exciton lifespan. GQD-N-TiO2-300 revealed higher surface area (191.91m2 g−1), pore diameter (1.94 nm), TEM particle size distribution (4.88 ± 1.26 nm) with lattice spacing of 0.45 nm and bandgap (2.91 eV). In addition, GQDs incorporation shifted XPS spectrum of Ti 2p to lower binding energy level (458.36 eV), while substitution of oxygen sites in TiO2 lattice by carbon were confirmed through deconvolution of C 1 s spectrum. Photocatalytic reaction followed the pseudo first order reaction and continuous reductions in apparent rate constant (Kapp) with incremental increase in RB5 concentration. Langmuir–Hinshelwood model showed surface reaction rate constants KC = 1.95 mg L−1 min−1 and KLH = 0.76 L mg−1. The active species trapping, and mechanism studies indicated the photocatalytic decolorization of RB5 through GQD-N-TiO2 was governed by type II heterojunction. Overall, the photodecolorization reactions were triggered by the formation of holes and reactive oxygen species. The presence of •OH, 1O2, and O2• during the photocatalytic process were confirmed through EPR analysis. The excellent photocatalytic decolorization of the synthesized nanocomposite against RB5 can be ascribed to the presence of GQDs in the TiO2 lattice that acted as excellent electron transporter and photosensitizer. This study provides a basis for using nonmetal, abundant, and benign materials like graphene quantum dots to enhance the TiO2 photocatalytic efficiency, opening new possibilities for environmental applications. [ABSTRACT FROM AUTHOR]