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    Bodipy/dipyridylamino-based "turn-on" fluorescent chemosensor for trivalent chromium cations: characterization and photophysical properties
    (ROYAL SOC CHEMISTRY, 2015) Kursunlu, Ahmed Nuri; Sahin, Emel; Guler, Ersin
    {{3,5-Bis[4,4-difluoro, 8-(2,6-diethyl,1,3,5,7-tetramethyl-4-bora-3a, 4a-diaza-s-indacene)]}}phenyl-N,N-di( pyridin-2-yl) benzamide (Bodipy-DPy) was designed as an efficient fluorescent chemosensor for Cr(III). The structure of Bodipy-DPy was confirmed by UV-vis spectroscopy, fluorometry, melting point analysis, H-1-NMR, C-13-NMR, elemental analysis and ESI-TOF-MS. Its photophysical properties was investigated by absorption, emission and excitation techniques. Based on chelation assisted fluorescence enhancement, a fluorometric method was developed for trace level detection, selectivity and concentration studies of chromium(III) in EtOH-H2O. The fluorescent ligand behaved as a chemosensor for Cr(III) cations and showed a strong red fluorescence upon coordination with Cr(III), whereas almost no fluorescence was observed for the other metal cations studied. The Bodipy-DPy has absorption and emission maxima at 528 nm and 535 nm, respectively. The equilibrium binding constant of Bodipy-DPy with Cr(III) was calculated as 1.17 x 10(6) from the Stern-Volmer equation.
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    Cu (II) Chemosensor Based on a Fluorogenic Bodipy-Salophen Combination: Sensitivity and Selectivity Studies
    (SPRINGER/PLENUM PUBLISHERS, 2016) Kursunlu, Ahmed Nuri; Sahin, Emel; Guler, Ersin
    A new fluorescent chemosensor (Bodipy-S) derived from Bodipy and Salophen was developed. After the characterization of all compounds, the behavior of the chemosensor Bodipy-S toward p, d and f block-metal ions was investigated by UV-vis and fluorescence spectroscopy. This chemosensor can selectively detect to Cu (II) in methanol-aqueous solution based on chelation enhanced fluorescence (CHEF) and it almost exhibit to a fluorescence quenching effect with 20-fold. The binding constant of the fluorophore was interpreted by using of the Stern-Volmer method and the complex stoichiometry was defined by using Job's plot. Moreover, the effect of pH was performed by the fluorescence intensities of Bodipy-S in presence of Cu(II) ions. The chemosensor can be successfully used to the detection of Cu(II) in most areas.
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    Increased ischemia-modified albumin and malondialdehyde levels in videothoracoscopic surgery
    (WOLTERS KLUWER MEDKNOW PUBLICATIONS, 2016) Oncel, Muide; Kiyici, Aysel; Oncel, Murat; Sunam, Guven Sadi; Sahin, Emel; Adam, Bahattin
    BACKGROUND: Videothoracoscopic surgery leads to general organ hypoperfusion by reducing mean arterial pressure, systemic vascular resistance, and end-diastolic volume index. Oxidative stress occurs as a result of hypoperfusion. Evaluation of the short-term effects of videothoracoscopic sympathectomy on serum ischemia-modified albumin (IMA), malondialdehyde (MDA), and nitric oxide (NO) levels in patients with primary hyperhidrosis was aimed. METHODS: Twenty-six patients who underwent videothoracoscopic surgery were contributed in this study. Venous blood samples were obtained from these patients 1 h before and after the surgery. IMA, MDA, and NO levels were measured in serum samples by colorimetric methods. Albumin concentrations were also measured for each sample, and albumin-adjusted IMA levels were calculated. RESULTS: Postoperative IMA, albumin-adjusted IMA, and MDA values were significantly higher compared to the preoperative values (P = 0.003, 0.027, 0.018, respectively). However, postoperative NO levels were lower than the preoperative values (P = 0.002). There was no significant difference between pre- and postoperative albumin concentrations, and there was no significant correlation between the parameters tested. CONCLUSIONS: We can conclude that elevation in MDA and IMA levels after videothoracoscopic surgery was caused by increased oxidative stress due to minimal ischemia-reperfusion injury after the infusion of CO 2 during the surgical process. Videothoracoscopic sympathectomy operation causes a decrease in NO production, and this should be taken in consideration when evaluating nitrosative stress in videothoracoscopic surgery.