Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 23Citation - Scopus: 23Bodipy-Vinyl Dibromides as Triplet Sensitisers for Photodynamic Therapy and Triplet-Triplet Annihilation Upconversion(Royal Society of Chemistry, 2021) Dartar, Suay; Emrullahoğlu, Mustafa; Karakuş, Erman; Hou, Yuqi; Zhao, Jianzhang; Emrullahoğlu, Mustafa; 04.01. Department of Chemistry; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyWe devised a new generation of halogen-based triplet sensitisers comprising geminal dibromides at the vinyl backbone of a BODIPY fluorophore. Incorporating geminal dibromides into the pi-conjugation of BODIPY enhanced intersystem crossing due to the heavy atom effect, which in turn improved the extent of excited triplet states.Article Citation - WoS: 36Citation - Scopus: 37A Bodipy-Based Fluorescent Probe for Ratiometric Detection of Gold Ions: Utilization Of: Z -Enynol as the Reactive Unit(Royal Society of Chemistry, 2016) Üçüncü, Muhammed; Karakuş, Erman; Emrullahoğlu, Mustafa; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyUsing an irreversible intramolecular cyclisation pathway triggered by gold ions, a boron-dipyrromethene (BODIPY) based fluorescent probe integrated with a reactive Z-enynol motif responds selectively to gold ions. With the addition of gold(iii), the probe displays ratiometric fluorescence behaviour clearly observable to the naked eye under both visible and UV light. © The Royal Society of Chemistry 2016.Article Citation - WoS: 33Citation - Scopus: 36Epr Studies of Intermolecular Interactions and Competitive Binding of Drugs in a Drug-Bsa Binding Model(Royal Society of Chemistry, 2016) Akdoğan, Yaşar; Emrullahoğlu, Mustafa; Akdoğan, Yaşar; Üçüncü, Muhammed; Çakan Akdoğan, Gülçin; Emrullahoğlu, Mustafa; 03.09. Department of Materials Science and Engineering; 04.04. Department of Photonics; 03. Faculty of Engineering; 04. Faculty of Science; 01. Izmir Institute of TechnologyUnderstanding intermolecular interactions between drugs and proteins is very important in drug delivery studies. Here, we studied different binding interactions between salicylic acid and bovine serum albumin (BSA) using electron paramagnetic resonance (EPR) spectroscopy. Salicylic acid was labeled with a stable radical (spin label) in order to monitor its mobilized (free) or immobilized (bound to BSA) states. In addition to spin labeled salicylic acid (SL-salicylic acid), its derivatives including SL-benzoic acid, SL-phenol, SL-benzene, SL-cyclohexane and SL-hexane were synthesized to reveal the effects of various drug binding interactions. EPR results of these SL-molecules showed that hydrophobic interaction is the main driving force. Whereas each of the two functional groups (-COOH and -OH) on the benzene ring has a minute but detectable effect on the drug-protein complex formation. In order to investigate the effect of electrostatic interaction on drug binding, cationic BSA (cBSA) was synthesized, altering the negative net charge of BSA to positive. The salicylic acid loading capacity of cBSA is significantly higher compared to that of BSA, indicating the importance of electrostatic interaction in drug binding. Moreover, the competitive binding properties of salicylic acid, ibuprofen and aspirin to BSA were studied. The combined EPR results of SL-salicylic acid/ibuprofen and SL-ibuprofen/salicylic acid showed that ibuprofen is able to replace up to ∼83% of bound SL-salicylic acid, and salicylic acid can replace only ∼14% of the bound SL-ibuprofen. This indicates that ∼97% of all salicylic acid and ibuprofen binding sites are shared. On the other hand, aspirin replaces only ∼23% of bound SL-salicylic acid, and salicylic acid replaces ∼50% of bound SL-aspirin, indicating that ∼73% of all salicylic acid and aspirin binding sites are shared. These results show that EPR spectroscopy in combination with the spin labeling technique is a very powerful method to investigate drug binding dynamics in detail.Article Citation - WoS: 24Citation - Scopus: 27Physiological Concentrations of Albumin Favor Drug Binding(Royal Society of Chemistry, 2015) Tatlıdil, Diğdem; Üçüncü, Muhammed; Akdoğan, Yaşar; 03.09. Department of Materials Science and Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyThe ability to track drug binding and release makes electron paramagnetic resonance (EPR) spectroscopy well suited for drug delivery studies. Using the continuous wave (cw) EPR technique to extract information about the dynamics of the spin labeled drugs we can simultaneously determine the bound and unbound drugs. Here, spin labeled salicylic acid (SLSA) binding to and release from bovine serum albumin (BSA) is investigated, as a model for drug-transport protein interaction. We studied SLSA-BSA binding in a wide concentration range and found that the stoichiometry of the drug-protein increases significantly when the physiological range of BSA concentration is reached. Our EPR results explicitly reveal that up to ∼7 SLSA can bind to one albumin at the physiological concentration, whereas at lower BSA concentrations (<0.125 mM) the SLSA-BSA stoichiometry is maximum 2. Moreover, we studied drug release and showed that the ratio of bound to unbound SLSA concentrations remains relatively stable during dialysis. This indicates that the binding equilibrium of SLSA is not altered through the process of dialysis. This study demonstrates that cw EPR spectroscopy in combination with spin labeled drugs is an effective technique for binding and release studies and stoichiometric analysis of drug-protein interactions.Article Citation - WoS: 5Citation - Scopus: 5A Rare ?-Pyranopyrazole Skeleton: Design, One-Pot Synthesis and Computational Study(Royal Society of Chemistry, 2016) Üçüncü, Muhammed; Cantürk, Ceren; Emrullahoğlu, Mustafa; Zeybek, Hüseyin; Bozkaya, Uğur; Soydaş, Emine; Şahin, Ertan; Emrullahoğlu, Mustafa; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyDrawing upon a consecutive amide coupling and intramolecular cyclisation pathway, a one-pot, straightforward synthetic route has been developed for a range of pyrazole fused γ-pyrone derivatives. The reaction mechanism proposed for the chemoselective formation of γ-pyranopyrazole is furthermore fully supported by experimental and computational studies. © The Royal Society of Chemistry 2016.Article Citation - WoS: 22Citation - Scopus: 25A Bodipy/Pyridine Conjugate for Reversible Fluorescence Detection of Gold(iii) Ions(Royal Society of Chemistry, 2015) Üçüncü, Muhammed; Karakuş, Erman; Emrullahoğlu, Mustafa; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyWe designed a "turn-on" type fluorescent probe based on a BODIPY-pyridine conjugate which exhibits high selectivity towards Au(iii) ions and, also responds to changes in the pH within the acidic pH range. The probe offers features such as a rapid response time, a low detection limit, and high sensitivity and selectivity. The detection of Au(iii) is recognized by a distinct change in the emission intensity which relies on a reversible "ligand to ion" binding mechanism. We also document the utility of the probe for the quantification of gold ion residues in synthetic end products prepared via gold catalysis. © 2015 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.Article Citation - WoS: 43Citation - Scopus: 43A Bodipy-Based Fluorescent Probe for the Differential Recognition of Hg(ii) and Au(iii) Ions(Royal Society of Chemistry, 2015) Cantürk, Ceren; Üçüncü, Muhammed; Emrullahoğlu, Mustafa; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyWe describe the design, synthesis and spectral behaviour of a fluorescent molecular sensor able to recognize Hg2+ and Au3+ ions via different emission modes. The molecular sensor is constructed on a single BODIPY dye appended with a semithio-carbazone functionality as a recognition motif.Article Citation - WoS: 118Citation - Scopus: 121A Rhodamine/Bodipy-Based Fluorescent Probe for the Differential Detection of Hg(II) and Au(III)(Royal Society of Chemistry, 2014) Karakuş, Erman; Üçüncü, Muhammed; Emrullahoğlu, Mustafa; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyWe described the design and synthesis of a molecular sensor based on a rhodamine/BODIPY platform that displayed differential fluorescence responses towards Hg2+ and Au3+ and demonstrated its utility in intracellular ion imaging.Article Citation - WoS: 20Citation - Scopus: 22A New Proton Sponge Polymer Synthesized by Raft Polymerization for Intracellular Delivery of Biotherapeutics(Royal Society of Chemistry, 2014) Kurtuluş, Işıl; Yılmaz, Gökhan; Bulmuş Zareie, Volga; Emrullahoğlu, Mustafa; Becer, C. Remzi; Emrullahoğlu, Mustafa; 04.04. Department of Photonics; 03.01. Department of Bioengineering; 03. Faculty of Engineering; 04. Faculty of Science; 01. Izmir Institute of TechnologyA spermine-like polymer was synthesized via reversible addition- fragmentation chain transfer polymerization as a potential endosomal escaping agent. A new methacrylate monomer, 2-((tert-butoxycarbonyl)(2-((tert- butoxycarbonyl)amino)ethyl)amino)ethylmethacrylate (BocAEAEMA), was prepared and then polymerized via RAFT polymerization at constant monomer or initiator concentration at varying [M]/[R]/[I] ratios. In all polymerizations, ln[M] 0/[M] increased linearly with time. The linear increase in M n with monomer conversion was also observed. P(BocAEAEMA)s with controlled molecular weights and narrow molecular weight distributions were obtained. The in vitro cytotoxicity and proton sponge capacity of deprotected polymers P(AEAEMA) were investigated in comparison with a widely used endosomal-disruptive polymer, PEI. P(AEAEMA)s were found to possess proton sponge capacity comparable with PEI. More importantly, P(AEAEMA)s were not toxic on NIH 3T3 cells at concentrations where PEI (25 kDa) was highly toxic (0.4 μM and above). P(AEAEMA) was able to fully condense a DNA fragment at nitrogen/phosphate (N/P) ratios of 10 and above, as evidenced by gel electrophoresis. P(BocAEAEMA) was then chain-extended with a model sugar monomer, mannose-acrylate (ManAc), to yield P(AEAEMA)-b-P(ManAc) block copolymers, to potentially provide cell-recognition ability to the polyplex particles. Although the presence of the P(ManAc) block partially inhibited the interaction of P(AEAEMA) with DNA, P(AEAEMA)13-b-P(ManAc)7 was able to form polyplexes with DNA at N/P ratios ranging between 20/1 and 2/1. Dynamic light scattering measurements showed that while P(AEAEMA) (M n = 5.5 kDa) and DNA formed polyplex particles having a hydrodynamic diameter (Dh) of 125 ± 51 nm, P(AEAEMA)13-b- P(ManAc)7 and DNA formed particles with a smaller Dh of 38 ± 10 nm.Article Citation - WoS: 60Citation - Scopus: 62A Bodipy-Based Reactive Probe for the Detection of Au(iii) Species and Its Application To Cell Imaging(Royal Society of Chemistry, 2014) Üçüncü, Muhammed; Emrullahoğlu, Mustafa; Emrullahoğlu, Mustafa; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyA BODIPY-based fluorescent probe bearing a pyridyl hydrazone motif responds selectively to Au(III) ions through an irreversible C[double bond, length as m-dash]N bond hydrolysis reaction. Gold species, besides their ability to catalyse chemical transformations in organic synthesis,1 have significant impacts on human health.2,3 Gold-based drugs have long been used in the treatment of rheumatoid arthritis and other autoimmune diseases.2 At the same time, when accumulated in the biological system at certain concentrations, gold species have the potential to disturb a series of cellular processes by irreversible interaction with biomolecules.3 In recent years, fluorescence-based sensing has become an indispensable tool for sensitive and accurate detection of trace levels of metal species in the solution.4 In addition, with the aid of fluorescence microscopy it has become possible to track metal species in living cells, which is of crucial importance for elucidating their roles in the biological system.