Partitioning of quinapril anion between cetyltrimethylammonium bromide micelles and water

The interaction of the anion of quinapril (QUIN), angiotensin converting enzyme (ACE) inhibitor, with cationic surfactant cetyltrimethylammonium bromide (CTAB) was studied as a model system for drug/membrane interactions. From the dependence of differential absorbance at λ=272 nm on CTAB concentration, by using mathematical model that treats the solubilization of QUIN anion as its binding to specific sites in the micelles (Langmuir adsorption isotherm), the binding constant Kb was obtained.Physical chemistry 2006 : 8th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 26-29 September 200

Surface modification of TiO2 nanoparticles with catechol

Surface modification of nanocrystalline TiO2 particles with catechol was found to result in a red shift of the semiconductor absorption compared to unmodified nanocrystallites. The undercoordinated defect sites at TiO2 surface are the source of novel enhanced and selective reactivity of the nanoparticle toward bidentate ligand binding. Catechol, an enediol ligand, have the optimal geometry for chelating surface Ti atoms, resulting in a five-membered ring coordination complex and restoration of six-coordinated octahedral geometry of surface Ti atoms.Physical chemistry 2008 : 9th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 200

Derivative spectrophotometric determination of partition coefficient of hydrochlorothiazide between cetyltrimethylammonium bromide micelles and water

The interaction of hydrochlorothiazide (HCT), benzothiadiazine diuretic, with cationic surfactant cetyltrimethylammonium bromide (CTAB) was studied as a model system for drug/membrane interactions. From the dependence of first order derivative amplitude 1 D250.1 on CTAB concentration, by using mathematical models based on the partition of the drug between micellar and aqueous pseudo-phase, CTAB/water partition coefficient Kp was calculated.Physical chemistry 2004 : 7th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 21-23 September 200

Characterization of dosimeters used in radiation processing

Aérial L-alanine pellet dosimeter is characterized as the dispersion of dose measurement values in order to determine the level of uncertainty caused by dosimeter itself. The results of repeated measurements indicate that the uncertainty of 1.2% could be attributed to the homogeneity of alanine in dosimeter pellets. It was obtained by analyzing the results of measurements of the different dosimeters from the same batch that the uncertainty due to difference in dosimeter mass is 1%. The total uncertainty due to dosimeter itself is 1.5%.Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 201

Structural characterization of bio-modified epoxy resin by using MALDI-TOF

Polymers and polymer composites have wide application in every industrial field, and are a subject of continuous research from different scientific aspects [1,2]. However, most commercial polymers are oil refinery based products. Recently, due to a growing concern for oil depletion, researchers have been focused on modification of polymers, as well as reinforcements [3,4]. Epoxy resin is the most commonly used adhesive that can be improved with fiber or particle reinforcements, or by using chemical modifiers. Modifying agents from renewable resources show potential in replacing oil-based compounds, because of their abundance, low price and heterogeneous structure that offers number of reactive groups [5]. In our research, honey was used as a bio-based modifier for diglycidyl ether of bisphenolA (DGEBA) based epoxy resin, with the aim of investigating structural changes. MALDI-TOF mass spectrometry [6] was used as a powerful technique that is able to reveal presence of functional groups and modified epoxy resin structure. In this manner, successful chemical modification of epoxy resin was confirmed, which further opened the path for the investigation of honey potential as epoxy modifying agent.9. Simpozijum "Hemija i zaštita životne sredine" sa međunarodnim učešćem : Knjiga izvoda ; 4-7. jun 2023; Kladovo, Srbija9th Symposium Chemistry and Environmental Protection with international participation : Book of Abstracts ; 4-7th June 2023 ; Kladovo, Serbi

Surface modification of anatase nanoparticles with substituted catecholate type ligands

The surface modification of nanocrystalline TiO2 particles (45 Å) with catecholate-type ligands having electron donating (4-methylcatechol, 4MetCat) and electron withdrawing (4-nitrocatechol, 4NitCat) substituent groups, was found to alter the optical properties of nanoparticles in a similar way to catechol (Cat). The formation of the inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption onset compared to unmodified nanocrystallites, being slightly less pronounced in the case of electron withdrawing substituent. The investigated ligands have the optimal geometry for binding to surface Ti atoms, resulting in ring coordination complexes of catecholate type (binuclear bidentate binding - bridging) thus restoring six-coordinated octahedral geometry of surface Ti atoms. The binding structures were investigated by using FTIR spectroscopy

Surface modification of zirconia nanoparticles with selected enediol ligands

The colloidal ZrO2 nanoparticles were hydrolytically synthesized and characterized using x-ray diffraction and UV/Vis spectroscopy. The surface modification of nanocrystalline particles with selected enediol ligands: catechol (CAT), 2,3-dihydroxynaphthalene (2,3-DHN), anthrarobin (ANT) and quercetin, was found to alter the optical properties of nanoparticles. The formation of the inner-sphere charge-transfer (CT) complexes results in a red shift of the semiconductor absorption onset compared to unmodified nanocrystallites, and a decrease of effective band gap upon increase of the electron delocalization after the inclusion of additional ring

Supplementary data for the article: Savić, T. D.; Ćomor, M. I.; Abazović, N. D.; Šaponjić, Z. V.; Marinović-Cincović, M. T.; Veljković, D. Ž.; Zarić, S. D.; Janković, I. A. Anatase Nanoparticles Surface Modified with Fused Ring Salicylate-Type Ligands (1-Hydroxy-2-Naphthoic Acids): A Combined DFT and Experimental Study. Journal of Alloys and Compounds 2015, 630, 226–235. https://doi.org/10.1016/j.jallcom.2015.01.041

Supplementary material for: [https://doi.org/10.1016/j.jallcom.2015.01.041]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1661

Supplementary data for article: Savić, T. D.; Šaponjić, Z. V.; Čomor, M. I.; Nedeljkovic, J. M.; Dramicanin, M. D.; Nikolić, M. G.; Veljković, D. Ž.; Zarić, S.; Janković, I. A. Surface Modification of Anatase Nanoparticles with Fused Ring Salicylate-Type Ligands (3-Hydroxy-2-Naphthoic Acids): A Combined DFT and Experimental Study of Optical Properties. Nanoscale 2013, 5 (16), 7601–7612. https://doi.org/10.1039/c3nr01277h

Supplementary material for: [https://doi.org/10.1039/c3nr01277h]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1590

Synthesis of core-shell NaYF4:Yb,Tm@TiO2-Acacc micro- and nano-sized particles for efficient photocatalysis

Micro- and nano-sized core-shell particles for efficient photocatalysis were successfully synthesized by a two step wet-chemical route. The core composed of up-converting (UC) NaYF4:Yb,Tm phase was prepared through EDTA assisted hydrothermal process, while the shell of anatase TiO2 –Acetylacetone (TiO2-Acac) charge-transfer complex was formed via a sol-gel method. During coating, the effect of polyvinylpyrrolidone (PVP) addition on the core and shell coupling was investigated. Two forms of core structures were obtained: hexagonal microprisms of -NaYF4:Yb,Tm and -NaYF4:Yb,Tm nanospheres, both coated with TiO2-Acac nanocrystals