Yazar "Ozsamur, Nezahat Gokce" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    Catalytic investigation of hyaluronic acid-stabilized Ag nanoparticles as non-toxic nanocatalysts in the oxidation of morin
    (Royal Soc Chemistry, 2024) Yilmaz, M. Deniz; Ozsamur, Nezahat Gokce; Erbas-Cakmak, Sundus
    Catalytic oxidation is a widely used technology to eliminate undesired organic substances from water resources. Transition metal catalysts have a critical role to play in catalytic advanced oxidation; however, the toxicity of these catalysts is a major threat to human health and the environment. Therefore, research on the development of efficient oxidation catalysts with reduced toxicity is extremely critical. Herein, we report the catalytic investigation of hyaluronic acid-functionalized silver nanoparticles (HA-AgNPs) as an efficient and non-toxic catalyst in the degradation of morin dye as a model compound. The as-synthesized nanoparticles are characterized by different analytical methods such as ultraviolet-visible (UV-vis) spectroscopy, scanning transmission electron microscopy (STEM), X-ray diffraction (XRD), dynamic light scattering (DLS) and zeta potential. The particle size and charge of the HA-AgNPs are found to be 23.9 +/- 8.3 nm and -43.5 +/- 0.8 mV, respectively. The catalytic activity of HA-AgNPs has been assessed in the oxidation of morin with H2O2. The catalytic studies reveal that the oxidation follows first order reaction kinetics with an apparent rate constant of 1.01 x 10-2 s-1 and the degradation of morin has been completed within 5 min, indicating outstanding catalytic properties of HA-AgNPs. The cytotoxicity of HA-AgNPs was further evaluated by MTT assay and the results show that these nanoparticles are non-toxic to MCF-10A non-tumorigenic breast epithelial cells and MCF-7 breast cancer cells. We report hyaluronic acid-stabilized Ag nanoparticles as highly efficient and nontoxic oxidation nanocatalysts for the first time.
  • Küçük Resim Yok
    Öğe
    Reprograming cancer cells by a BODIPY G-quadruplex stabiliser
    (Royal Soc Chemistry, 2023) Baser, Aminesena; Basar, Beyza; Dogan, Hanim Beyza; Sener, Gulnur; Ozsamur, Nezahat Gokce; Celik, Fatma Secer; Altves, Safaa
    A cationic BODIPY-based G-quadruplex-selective stabiliser is developed and shown to decrease cancer cell migration-invasion up to 90%. The expression of critical genes (HIF1 alpha, VIM, CDH1) related to metastasis is modulated. The stabiliser reprograms hypoxia-adaptive metabolism and an 1.82-fold increase in O2 consumption, enabling back-to-normal switching of energy metabolism, is observed. Stabilisers with a strong G-quadruplex affinity (0.38 mu M Kd) significantly contribute to small molecule anti-cancer approaches. A BODIPY-based G-quadruplex-selective stabiliser is shown to silence regulator genes, reduce cell migration and invasion, and switch off the hypoxia-adaptive metabolism.