TY - JOUR AU - Vancza, Andor AU - Kapta, Marcell Levente AU - Papp, Mariann AU - Vankó, György AU - Keszthelyi, Tamás TI - Determining the Quintet Lifetimes in Side-ring Substituted [Fe(terpy)2]2+ Complexes JF - PERIODICA POLYTECHNICA-CHEMICAL ENGINEERING J2 - PERIOD POLYTECH CHEM ENG VL - 67 PY - 2023 IS - 4 SP - 547 EP - 556 PG - 10 SN - 0324-5853 DO - 10.3311/PPch.22748 UR - https://m2.mtmt.hu/api/publication/34400257 ID - 34400257 N1 - Export Date: 08 March 2024 LA - English DB - MTMT ER - TY - JOUR AU - Papp, Mariann AU - Keszthelyi, Tamás AU - Vancza, Andor AU - Bajnóczi, Éva Gabriella AU - Kováts, Éva AU - Németh, Zoltán AU - Kovácsné Bogdán, Csilla AU - Bazsó, Gábor AU - Rozgonyi, Tamás AU - Vankó, György TI - Molecular Engineering to Tune Functionality: The Case of Cl-Substituted [Fe(terpy)2]2+ JF - INORGANIC CHEMISTRY J2 - INORG CHEM VL - 62 PY - 2023 IS - 16 SP - 6397 EP - 6410 PG - 14 SN - 0020-1669 DO - 10.1021/acs.inorgchem.3c00271 UR - https://m2.mtmt.hu/api/publication/33763197 ID - 33763197 N1 - Export Date: 14 March 2024 CODEN: INOCA LA - English DB - MTMT ER - TY - JOUR AU - Szemes, Dorottya AU - Keszthelyi, Tamás AU - Papp, Mariann AU - Varga, L AU - Vankó, György TI - Quantum-chemistry-aided ligand engineering for potential molecular switches: changing barriers to tune excited state lifetimes JF - CHEMICAL COMMUNICATIONS J2 - CHEM COMMUN VL - 56 PY - 2020 IS - 79 SP - 11831 EP - 11834 PG - 4 SN - 1359-7345 DO - 10.1039/D0CC04467A UR - https://m2.mtmt.hu/api/publication/31595664 ID - 31595664 N1 - Export Date: 14 March 2024 CODEN: CHCOF LA - English DB - MTMT ER - TY - JOUR AU - Keszthelyi, Tamás AU - Holló, Gábor AU - Nyitrai, Gabriella AU - Kardos, Julianna AU - Héja, László TI - Bilayer Charge Reversal and Modification of Lipid Organization by Dendrimers as Observed by Sum-Frequency Vibrational Spectroscopy JF - LANGMUIR J2 - LANGMUIR VL - 31 PY - 2015 IS - 28 SP - 7815 EP - 7825 PG - 11 SN - 0743-7463 DO - 10.1021/acs.langmuir.5b00734 UR - https://m2.mtmt.hu/api/publication/2932290 ID - 2932290 N1 - Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, Budapest, H-1117, Hungary Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, Budapest, H-1117, Hungary Cited By :9 Export Date: 7 April 2021 CODEN: LANGD Correspondence Address: Keszthelyi, T.; Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, Hungary AB - Polyamidoamine (PAMAM) dendrimers are hyper-branched, nanosized polymers with promising biomedical applications as nanocarriers in targeted drug delivery and gene therapy. For the development of safe dendrimer-based biomedical applications it is necessary to gain an understanding of the detailed mechanism of the interactions of both cationic and anionic dendrimers with cell membranes. To characterize dendrimer membrane interactions we applied solid-supported lipid bilayers as biomembrane models and utilized infrared visible sum-frequency vibrational spectroscopy to independently probe the interactions of cationic G5-NH2 and anionic G4.5-COONa dendrimers with the two leaflets of the lipid bilayers. Interaction with both dendrimers led to changes in the interfacial water structure and charge density as evidenced by the changes in the OH band intensities in the sum-frequency spectra of the bilayers. Interaction with the G5-NH2 dendrimer also led to a unique inversion of the sign of the OH-stretch amplitudes, in addition to a decrease in their absolute values. We suggest that the positively charged amino groups on the G5-NH2 dendrimer surface bind to the negatively charged bilayer, while uncompensated positive charges not involved in the binding cause a reversal of the electric field and thus an opposite orientation of the interfacial water molecules. More subtle but nonetheless significant changes were seen in the relative magnitudes of the CH amplitudes. The methyl antisymmetric to symmetric stretch amplitude ratios are altered, implying changes in the tilt angles of the phospholipid alkyl chains. The conformational order of the phospholipid alkyl chains of both leaflets is also influenced by the G5-NH2 dendrimer while G4.5-COONa has no effect on the alkyl chain conformation. LA - English DB - MTMT ER - TY - JOUR AU - Keszthelyi, Tamás AU - Hill, Katalin AU - Kiss, Éva TI - Interaction of Phospholipid Langmuir Monolayers with an Antibiotic Peptide Conjugate JF - JOURNAL OF PHYSICAL CHEMISTRY B J2 - J PHYS CHEM B VL - 117 PY - 2013 IS - 23 SP - 6969 EP - 6979 PG - 11 SN - 1520-6106 DO - 10.1021/jp401533c UR - https://m2.mtmt.hu/api/publication/2334513 ID - 2334513 N1 - Cited By :10 Export Date: 26 November 2019 CODEN: JPCBF Correspondence Address: Keszthelyi, T.; Institute of Molecular Pharmacology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Pusztaszeri út 59-67, H-1025 Budapest, Hungary; email: keszthelyi.tamas@ttk.mta.hu LA - English DB - MTMT ER - TY - JOUR AU - Nyitrai, Gabriella AU - Keszthelyi, Tamás AU - Bóta, Attila AU - Simon, Ágnes AU - Tőke, Orsolya AU - Horváth, Gergő AU - Pál, Ildikó AU - Kardos, Julianna AU - Héja, László TI - Sodium selective ion channel formation in living cell membranes by polyamidoamine dendrimer JF - BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES J2 - BBA-BIOMEMBRANES VL - 1828 PY - 2013 IS - 8 SP - 1873 EP - 1880 PG - 8 SN - 0005-2736 DO - 10.1016/j.bbamem.2013.04.004 UR - https://m2.mtmt.hu/api/publication/2305528 ID - 2305528 N1 - Megjegyzés-23246857 N1 : Chemicals/CAScalcium ion, 14127-61-8; dipalmitoylphosphatidylcholine, 2644-64-6; silicon dioxide, 10279-57-9, 14464-46-1, 14808-60-7, 15468-32-3, 60676-86-0, 7631-86-9; sodium ion, 17341-25-2 LA - English DB - MTMT ER - TY - JOUR AU - Iavicoli, Patrizia AU - Xu, Hong AU - Keszthelyi, Tamás AU - Telegdi, Lászlóné AU - Wurst, Klaus AU - Van, Averbeke Bernard AU - Saletra, Wojciech J AU - Minoia, Andrea AU - Beljonne, David AU - Lazzaroni, Roberto AU - De Feyter, Steven AU - Amabilino, David B TI - Organization of the enantiomeric and racemic forms of an amphiphilic resorcinol derivative at the air–water and graphite–1-phenyloctane interfaces JF - CHIRALITY: THE PHARMACOLOGICAL BIOLOGICAL AND CHEMICAL CONSEQUENCES OF MOLECULAR ASYMMETRY J2 - CHIRALITY VL - 24 PY - 2012 IS - 2 SP - 155 EP - 166 PG - 12 SN - 0899-0042 DO - 10.1002/chir.21976 UR - https://m2.mtmt.hu/api/publication/1824179 ID - 1824179 N1 - CODEN: CHRLE LA - English DB - MTMT ER - TY - JOUR AU - Hill, Katalin AU - Pénzes, Csanád Botond AU - Schnöller, Donát AU - Horváti, Kata AU - Bősze, Szilvia AU - Hudecz, Ferenc AU - Keszthelyi, Tamás AU - Kiss, Éva TI - Characterisation of the membrane affinity of an isoniazide peptide conjugate by tensiometry, atomic force microscopy and sum-frequency vibrational spectroscopy, using a phospholipid Langmuir monolayer model JF - PHYSICAL CHEMISTRY CHEMICAL PHYSICS J2 - PHYS CHEM CHEM PHYS VL - 12 PY - 2010 IS - 37 SP - 11498 EP - 11506 PG - 9 SN - 1463-9076 DO - 10.1039/c002737e UR - https://m2.mtmt.hu/api/publication/1406707 ID - 1406707 LA - English DB - MTMT ER - TY - JOUR AU - Pászti, Zoltán AU - Hakkel, Orsolya AU - Keszthelyi, Tamás AU - Berkó, András AU - Balázs, Nándor AU - Bakó, Imre AU - Guczi, László TI - Interaction of Carbon Monoxide with Au(111) Modified by Ion Bombardment: A Surface Spectroscopy Study under Elevated Pressure JF - LANGMUIR J2 - LANGMUIR VL - 26 PY - 2010 IS - 21 SP - 16312 EP - 16324 PG - 13 SN - 0743-7463 DO - 10.1021/la1014913 UR - https://m2.mtmt.hu/api/publication/1406706 ID - 1406706 N1 - [2.32][2.1][2.53][3.61] AB - Gold based model systems exhibiting the structural versatility of nanoparticle ensembles and being accessible for surface spectroscopic investigations are expected to provide new information about the adsorption of carbon monoxide, a key process influencing the CO oxidation activity of this noble metal in nanoparticulate form. Accordingly, in the present work the interaction of CO is studied with an ion bombardment modified Au(111) surface by means of a combination of photoelectron spectroscopy (XPS and UPS), sum frequency generation vibrational spectroscopy (SFG), and scanning tunneling microscopy (STM). While no adsorption was found on intact Au(111), data collected on the ion bombarded surface at cryogenic temperatures indicated the presence of stable CO adsorbates below 190 K. A quantitative evaluation of the C 1s XPS spectra and the surface morphology explored by STM revealed that the step edge sites created by ion bombardment are responsible for CO adsorption. The identification of the CO binding sites was confirmed by density functional theory (DFT) calculations. Annealing experiments up to room temperature showed that at temperatures above 190 K unstable adsorbates are formed on the surface under dynamic exposure conditions that disappeared immediately when gaseous CO was removed from the system. Spectroscopic data as well as STM records revealed that prolonged CO exposure at higher pressures of up to 1 mbar around room temperature facilitates massive atomic movements on the roughened surface, leading to its strong reordering toward the structure of the intact Au(111) surface, accompanied by the loss of the CO binding capacity. © 2010 American Chemical Society. LA - English DB - MTMT ER - TY - JOUR AU - Hakkel, Orsolya AU - Pászti, Zoltán AU - Keszthelyi, Tamás AU - Frey, Krisztina AU - Guczi, László TI - Study of FeO(x)/Au inverse model catalysts by in situ sum frequency generation vibrational spectroscopy JF - REACTION KINETICS AND CATALYSIS LETTERS J2 - REACT KINET CATAL L VL - 96 PY - 2009 IS - 2 SP - 345 EP - 356 PG - 12 SN - 0133-1736 DO - 10.1007/s11144-009-5523-7 UR - https://m2.mtmt.hu/api/publication/113783 ID - 113783 N1 - CODEN: RKCLA AB - In this work a complex experimental setup is described which was developed by connecting an ultra-high vacuum multi-technique surface analysis system and a sum frequency generation vibrational spectrometer. This arrangement provides a unique environment to study interfaces under in situ conditions by a combination of complementary techniques. Preliminary results of CO adsorption experiments on gold and iron oxide thin layers grown on gold are presented as application examples of the experimental setup. LA - English DB - MTMT ER -