The Experts below are selected from a list of 126 Experts worldwide ranked by ideXlab platform
Gert Van Der Zwan - One of the best experts on this subject based on the ideXlab platform.
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pH-Dependent Complexation of Histamine H1 Receptor Antagonists and Human Serum Albumin Studied by UV Resonance Raman Spectroscopy
2016Co-Authors: Silvia Tardioli, Cees Gooijer, Joost Buijs, Gert Van Der ZwanAbstract:UV resonance Raman spectroscopy was used to characterize the binding of three first-generation histamine H1 receptor antagoniststripelennamine (TRP), mepyramine (MEP), and Brompheniramine (BPA)to human serum albumin (HSA) at pH 7.2 and pH 9.0. Binding constants differ at these pH values, which can be ascribed to the different extent of protonation of the ethylamino side chain of the ligands. We have recently shown [Tardioli et al. J. Raman Spectrosc. 2011, 42, 1016–1024] that for the solution conformation of TRP and MEP the side chain plays an important role by allowing an internal hydrogen bond with the aminopyridine nitrogen in TRP and MEP. Results presented in this paper suggest that the existence of such molecular structures has serious biological significance on the binding affinity of those ligands to HSA. At pH 7.2, only the stretched conformers of protonated TRP and MEP bind in HSA binding site I. Using UV absorption data, we derived binding constants for the neutral and protonated forms of TRP to HSA. The neutral species seems to be conjugated to a positive group of the protein, affecting both the tryptophan W214 and some of the tyrosine (Y) vibrations. BPA, for which the structure with an intramolecular hydrogen bonded side chain is not possible, is H bound to the indole ring nitrogen of W214, of which the side chain rotates over a certain angle to accommodate the drug in site I. We propose that the protonated BPA is also bound in site I, where the Y150 residue stabilizes the presence of this compound in the binding pocket. No spectroscopic evidence was found for conformational changes of the protein affecting the spectroscopic properties of W and Y in this pH range
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ph dependent complexation of histamine h1 receptor antagonists and human serum albumin studied by uv resonance raman spectroscopy
Journal of Physical Chemistry B, 2012Co-Authors: Silvia Tardioli, Joost B Buijs, Cees Gooijer, Gert Van Der ZwanAbstract:UV resonance Raman spectroscopy was used to characterize the binding of three first-generation histamine H1 receptor antagonists—tripelennamine (TRP), mepyramine (MEP), and Brompheniramine (BPA)—to human serum albumin (HSA) at pH 7.2 and pH 9.0. Binding constants differ at these pH values, which can be ascribed to the different extent of protonation of the ethylamino side chain of the ligands. We have recently shown [Tardioli et al. J. Raman Spectrosc.2011, 42, 1016–1024] that for the solution conformation of TRP and MEP the side chain plays an important role by allowing an internal hydrogen bond with the aminopyridine nitrogen in TRP and MEP. Results presented in this paper suggest that the existence of such molecular structures has serious biological significance on the binding affinity of those ligands to HSA. At pH 7.2, only the stretched conformers of protonated TRP and MEP bind in HSA binding site I. Using UV absorption data, we derived binding constants for the neutral and protonated forms of TRP t...
Silvia Tardioli - One of the best experts on this subject based on the ideXlab platform.
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pH-Dependent Complexation of Histamine H1 Receptor Antagonists and Human Serum Albumin Studied by UV Resonance Raman Spectroscopy
2016Co-Authors: Silvia Tardioli, Cees Gooijer, Joost Buijs, Gert Van Der ZwanAbstract:UV resonance Raman spectroscopy was used to characterize the binding of three first-generation histamine H1 receptor antagoniststripelennamine (TRP), mepyramine (MEP), and Brompheniramine (BPA)to human serum albumin (HSA) at pH 7.2 and pH 9.0. Binding constants differ at these pH values, which can be ascribed to the different extent of protonation of the ethylamino side chain of the ligands. We have recently shown [Tardioli et al. J. Raman Spectrosc. 2011, 42, 1016–1024] that for the solution conformation of TRP and MEP the side chain plays an important role by allowing an internal hydrogen bond with the aminopyridine nitrogen in TRP and MEP. Results presented in this paper suggest that the existence of such molecular structures has serious biological significance on the binding affinity of those ligands to HSA. At pH 7.2, only the stretched conformers of protonated TRP and MEP bind in HSA binding site I. Using UV absorption data, we derived binding constants for the neutral and protonated forms of TRP to HSA. The neutral species seems to be conjugated to a positive group of the protein, affecting both the tryptophan W214 and some of the tyrosine (Y) vibrations. BPA, for which the structure with an intramolecular hydrogen bonded side chain is not possible, is H bound to the indole ring nitrogen of W214, of which the side chain rotates over a certain angle to accommodate the drug in site I. We propose that the protonated BPA is also bound in site I, where the Y150 residue stabilizes the presence of this compound in the binding pocket. No spectroscopic evidence was found for conformational changes of the protein affecting the spectroscopic properties of W and Y in this pH range
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ph dependent complexation of histamine h1 receptor antagonists and human serum albumin studied by uv resonance raman spectroscopy
Journal of Physical Chemistry B, 2012Co-Authors: Silvia Tardioli, Joost B Buijs, Cees Gooijer, Gert Van Der ZwanAbstract:UV resonance Raman spectroscopy was used to characterize the binding of three first-generation histamine H1 receptor antagonists—tripelennamine (TRP), mepyramine (MEP), and Brompheniramine (BPA)—to human serum albumin (HSA) at pH 7.2 and pH 9.0. Binding constants differ at these pH values, which can be ascribed to the different extent of protonation of the ethylamino side chain of the ligands. We have recently shown [Tardioli et al. J. Raman Spectrosc.2011, 42, 1016–1024] that for the solution conformation of TRP and MEP the side chain plays an important role by allowing an internal hydrogen bond with the aminopyridine nitrogen in TRP and MEP. Results presented in this paper suggest that the existence of such molecular structures has serious biological significance on the binding affinity of those ligands to HSA. At pH 7.2, only the stretched conformers of protonated TRP and MEP bind in HSA binding site I. Using UV absorption data, we derived binding constants for the neutral and protonated forms of TRP t...
Zhen Jiang - One of the best experts on this subject based on the ideXlab platform.
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capillary electrophoretic enantioseparation of basic drugs using a new single isomer cyclodextrin derivative and theoretical study of the chiral recognition mechanism
IEEE Journal of Solid-state Circuits, 2016Co-Authors: Miaoduo Deng, Jia Yu, Zhen JiangAbstract:A novel single-isomer cyclodextrin derivative, heptakis {2,6-di-O-[3-(1,3-dicarboxyl propylamino)-2-hydroxypropyl]}-β-cyclodextrin (glutamic acid-β-cyclodextrin) was synthesized and used as a chiral selector in capillary electrophoresis for the enantioseparation of 12 basic drugs, including terbutaline, clorprenaline, tulobuterol, clenbuterol, procaterol, carvedilol, econazole, miconazole, homatropine methyl bromide, Brompheniramine, chlorpheniramine and pheniramine. The primary factors affecting separation efficiency, which include the background electrolyte pH, the concentration of glutamic acid-β-cyclodextrin and phosphate buffer concentration, were investigated. Satisfactory enantioseparations were obtained using an uncoated fused-silica capillary of 50 cm (effective length 40 cm) × 50 μm id with 120 mM phosphate buffer (pH 2.5-4.0) containing 0.5-4.5 mM glutamic acid-β-cyclodextrin as background electrolyte. A voltage of 20 kV was applied and the capillary temperature was kept at 20°C. The results proved that glutamic acid-β-cyclodextrin was an effective chiral selector for studied 12 basic drugs. Moreover, the possible chiral recognition mechanism of Brompheniramine, chlorpheniramine and pheniramine on glutamic acid-β-cyclodextrin was investigated using the semi-empirical Parametric Method 3.
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Effect of pH (A) and β-CD concentration (B) on RS of the 10 chiral analytes (1) zopiclone, (2) chlorphenamine maleate, (3) Brompheniramine maleate, (4) dioxopromethazine hydrochloride, (5) carvedilol, (6) homatropine hydrobromide, (7) homatropine met
2016Co-Authors: Linlin Fang, Zhen Jiang, Xingjie GuoAbstract:Effect of pH (A) and β-CD concentration (B) on RS of the 10 chiral analytes (1) zopiclone, (2) chlorphenamine maleate, (3) Brompheniramine maleate, (4) dioxopromethazine hydrochloride, (5) carvedilol, (6) homatropine hydrobromide, (7) homatropine methylbromide, (8) venlafaxine, (9) sibutramine hydrochloride and (10) terbutaline sulfate.
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Preparation of a β-Cyclodextrin-Based Open-Tubular Capillary Electrochromatography Column and Application for Enantioseparations of Ten Basic Drugs.
Public Library of Science (PLoS), 2024Co-Authors: Linlin Fang, Zhen Jiang, Xingjie GuoAbstract:An open-tubular capillary electrochromatography column was prepared by chemically immobilized β-cyclodextrin modified gold nanoparticles onto new surface with the prederivatization of (3-mercaptopropyl)-trimethoxysilane. The synthesized nanoparticles and the prepared column were characterized by transmission electron microscopy, scanning electron microscopy, infrared spectroscopy and ultraviolet visible spectroscopy. When the column was employed as the chiral stationary phase, no enantioselectivity was observed for ten model basic drugs. So β-cyclodextrin was added to the background electrolyte as chiral additive to expect a possible synergistic effect occurring and resulting in a better separation. Fortunately, significant improvement in enantioselectivity was obtained for ten pairs of drug enantiomers. Then, the effects of β-cyclodextrin concentration and background electrolyte pH on the chiral separation were investigated. With the developed separation mode, all the enantiomers (except for venlafaxine) were baseline separated in resolutions of 4.49, 1.68, 1.88, 1.57, 2.52, 2.33, 3.24, 1.63 and 3.90 for zopiclone, chlorphenamine maleate, Brompheniramine maleate, dioxopromethazine hydrochloride, carvedilol, homatropine hydrobromide, homatropine methylbromide, venlafaxine, sibutramine hydrochloride and terbutaline sulfate, respectively. Further, the possible separation mechanism involved was discussed
Cees Gooijer - One of the best experts on this subject based on the ideXlab platform.
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pH-Dependent Complexation of Histamine H1 Receptor Antagonists and Human Serum Albumin Studied by UV Resonance Raman Spectroscopy
2016Co-Authors: Silvia Tardioli, Cees Gooijer, Joost Buijs, Gert Van Der ZwanAbstract:UV resonance Raman spectroscopy was used to characterize the binding of three first-generation histamine H1 receptor antagoniststripelennamine (TRP), mepyramine (MEP), and Brompheniramine (BPA)to human serum albumin (HSA) at pH 7.2 and pH 9.0. Binding constants differ at these pH values, which can be ascribed to the different extent of protonation of the ethylamino side chain of the ligands. We have recently shown [Tardioli et al. J. Raman Spectrosc. 2011, 42, 1016–1024] that for the solution conformation of TRP and MEP the side chain plays an important role by allowing an internal hydrogen bond with the aminopyridine nitrogen in TRP and MEP. Results presented in this paper suggest that the existence of such molecular structures has serious biological significance on the binding affinity of those ligands to HSA. At pH 7.2, only the stretched conformers of protonated TRP and MEP bind in HSA binding site I. Using UV absorption data, we derived binding constants for the neutral and protonated forms of TRP to HSA. The neutral species seems to be conjugated to a positive group of the protein, affecting both the tryptophan W214 and some of the tyrosine (Y) vibrations. BPA, for which the structure with an intramolecular hydrogen bonded side chain is not possible, is H bound to the indole ring nitrogen of W214, of which the side chain rotates over a certain angle to accommodate the drug in site I. We propose that the protonated BPA is also bound in site I, where the Y150 residue stabilizes the presence of this compound in the binding pocket. No spectroscopic evidence was found for conformational changes of the protein affecting the spectroscopic properties of W and Y in this pH range
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ph dependent complexation of histamine h1 receptor antagonists and human serum albumin studied by uv resonance raman spectroscopy
Journal of Physical Chemistry B, 2012Co-Authors: Silvia Tardioli, Joost B Buijs, Cees Gooijer, Gert Van Der ZwanAbstract:UV resonance Raman spectroscopy was used to characterize the binding of three first-generation histamine H1 receptor antagonists—tripelennamine (TRP), mepyramine (MEP), and Brompheniramine (BPA)—to human serum albumin (HSA) at pH 7.2 and pH 9.0. Binding constants differ at these pH values, which can be ascribed to the different extent of protonation of the ethylamino side chain of the ligands. We have recently shown [Tardioli et al. J. Raman Spectrosc.2011, 42, 1016–1024] that for the solution conformation of TRP and MEP the side chain plays an important role by allowing an internal hydrogen bond with the aminopyridine nitrogen in TRP and MEP. Results presented in this paper suggest that the existence of such molecular structures has serious biological significance on the binding affinity of those ligands to HSA. At pH 7.2, only the stretched conformers of protonated TRP and MEP bind in HSA binding site I. Using UV absorption data, we derived binding constants for the neutral and protonated forms of TRP t...
Joost B Buijs - One of the best experts on this subject based on the ideXlab platform.
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ph dependent complexation of histamine h1 receptor antagonists and human serum albumin studied by uv resonance raman spectroscopy
Journal of Physical Chemistry B, 2012Co-Authors: Silvia Tardioli, Joost B Buijs, Cees Gooijer, Gert Van Der ZwanAbstract:UV resonance Raman spectroscopy was used to characterize the binding of three first-generation histamine H1 receptor antagonists—tripelennamine (TRP), mepyramine (MEP), and Brompheniramine (BPA)—to human serum albumin (HSA) at pH 7.2 and pH 9.0. Binding constants differ at these pH values, which can be ascribed to the different extent of protonation of the ethylamino side chain of the ligands. We have recently shown [Tardioli et al. J. Raman Spectrosc.2011, 42, 1016–1024] that for the solution conformation of TRP and MEP the side chain plays an important role by allowing an internal hydrogen bond with the aminopyridine nitrogen in TRP and MEP. Results presented in this paper suggest that the existence of such molecular structures has serious biological significance on the binding affinity of those ligands to HSA. At pH 7.2, only the stretched conformers of protonated TRP and MEP bind in HSA binding site I. Using UV absorption data, we derived binding constants for the neutral and protonated forms of TRP t...
