Yazar "Suner, Selin Sagbas" seçeneğine göre listele

Listeleniyor 1 - 3 / 3
  • [ X ]
    Öğe
    Gd(III) and Fe(III) ion crosslinked hyaluronic acid microgels composites embedding hetero atom doped carbon quantum dots render photodynamic therapy with improved bioimaging capability
    (Elsevier Science Sa, 2026) Suner, Selin Sagbas; Sahiner, Mehtap; Umut, Evrim; Sahiner, Nurettin
    In this study, we report the development of multifunctional CQ-dot@HA-Gd/Fe(III) microgels that can be readily simultaneously used in fluorescence/MR dual-mode imaging and photodynamic therapy as theragnostic agents. Nitrogen (N-) and sulfur (S-) heteroatom-doped carbon quantum dots (CQ-dot) were prepared in one step microwave treatment within 3 min as a fluorescence and photoinduced antipathogenic nanomaterial. The N/Sdoped CQ-dots were spherical shaped and < 50 nm via TEM images and showed high fluorescence intensity with 420 nm emission wavelength at maximum lambda(ex):350 nm. The N/S-doped CQ-dots were embedded into ionically crosslinked hyaluronic acid (HA) microgels, employing trivalent metal ions Gd(III) or Fe(III) ions. The prepared CQ-dot@HA-Gd/Fe(III) microgels <5 mm size range are injectable for possible intravenous administration and possess high fluorescent properties. The isoelectric point (IEP) of CQ-dot@HA-Gd and CQ-dot@HA-Fe (III) microgels was determined as pH 1.45. The CQ-dot@HA-Gd/Fe(III) microgels exhibit excellent hemocompatibility without causing noticeable hemolysis and blood clotting at concentrations up to 500 mg/mL. Furthermore, the toxicity of CQ-dot@HA-Gd/Fe(III) microgels on L929 fibroblast cells was found as 100 mg/mL concentration and provide brilliant cell imaging under DAPI filter without any fluorescence dye. Also, the CQdot@HA-Gd/Fe(III) microgel suspension afforded great MRI contrast enhancement ability. Photoinduced anticancer activity was observed for CQ-dot@HA-Gd/Fe(III) microgels even at 50 mg/mL against SK-MEL 30 melanoma cells under UV-A light treatment for 30 min. In addition, high reactive oxygen species (ROS) generation was obtained for the pathogenic bacteria cells by light-sensitive CQ-dot@HA-Gd/Fe(III) microgels upon 30 min UV-A light treatment that triggered the destruction of the Staphylococcus aureus (ATCC 6538).
  • [ X ]
    Öğe
    Poli(Rutin) Micro/nanogels for Biomedical Applications
    (2021) Şahiner, Mehtap; Suner, Selin Sagbas
    Flavonoids are natural phenolic compounds that are active molecules commonly found in woody and herbaceous plants and used in natural defense mechanisms of plants against harmful microorganisms. In this research, rutin (RUT) molecule which is a natural flavonoid was bounded with epoxy groups of poly(ethylene glycol) diglycidyl ether crosslinker by using micro emulsion crosslinking technique to synthesize of poly(rutin) (p(RUT)) micro/nanogels. These p(RUT) micro/nanogels showed spherical morphologic structure with 0.3 nm-2 µm dry size range due to scanning electron microscope image. Furthermore, p(RUT) micro/nanogels was found to be in injectable size range with 548±8.9 nm average size distribution in aqueous solution depends on the dynamic light scattering (DLS) measurement. In addition, the zeta potential measurements performed at different pH conditions and potentiometric titration of the prepared p(RUT) micro/nanogels was also determined and the isoelectronic point and pKa values of these micro/nanogels was estimated as pH 2.85 and 2.16, respectively. The effects of RUT and p(RUT) micro/nanogels on ?-glycosidase (AG) (EC 3.2.1.20) enzyme activity were investigated and it was found that RUT and p(RUT) micro/nanogels stimulate this enzyme. Moreover, fibrinogen interaction results showed that p(RUT) micro/nanogels were more compatible than RUT for vascular system with less interaction ability of fibrinogen of p(RUT) micro/nanogels. In addition, p(RUT) micro/nanogels observed highest antioxidant scavenging ability with 251.3±20.2 gallic acid equivalency total flavonoid content (TFC) at 250 µg/mL and reduced of 1.75±0.27 µmol Fe (III) even for 5 µg p(RUT) microgel/nanogels. Furthermore, no Fe (II) chelating activity was obtained for RUT monomer, but p(RUT) micro/nanogels showed significant Fe (II) chelating activity as 43.11±17.4 %.
  • [ X ]
    Öğe
    Single, Double, and Multiple-Heteroatoms Doped Carbon Quantum Dots as Effective Light-Induced Antimicrobial Materials
    (Springer/Plenum Publishers, 2025) Suner, Selin Sagbas; Sahiner, Mehtap; Demirci, Sahin; Sahiner, Nurettin
    Single-, dual-, and multi-heteroatoms such as N, S, and B-doped carbon quantum dots (CQ-dots) were prepared to determine their dopant effects on anti-pathogenic activities. The CQ-dots were prepared using maleic acid (MA), poly(vinyl amine) (PVAm), cysteine (Cys), and boric acid (BA) as carbon, nitrogen, sulfur, and boron sources, respectively. In 345-415 nm emission wavelength range, 45.9 +/- 2.4% quantum yield for dual heteroatom-doped (N/B-doped) CQ-dots were attained. Antimicrobial studies revealed that N-doped CQ-dots have significant antimicrobial susceptibility to both bacteria and fungi. The zeta potential value of N-doped CQDs had -4.9 mV was changed to -9.2 and -11.5 mV upon N/S- and N/B-doping, respectively. N/B-doped CQ-dots afforded the highest antibacterial activity providing a 1.56 mg/mL minimum inhibitory concentration (MIC) value against Escherichia coli, whereas N/S-doped CQ-dots had the highest antimicrobial activity against Staphylococcus aureus and Candida albicans yeast, 0.37 mg/mL MIC values. The photodynamic antimicrobial studies of N-, N/S-, N/B-, and N/S/B-doped CQ-dots significantly eradicated the bacteria and fungus colony upon UV-A light exposure for 30 min, with > 50% microbial colonial inhibitions. Both N and N/S-doped CQ-dots exhibit higher biofilm eradication/inhibition efficacy on Candida albicans biofilm, and all CQ-dots are biocompatible according to blood compatibility and cytotoxicity analysis at 1000 mu g/mL.