共查询到20条相似文献,搜索用时 31 毫秒
1.
Zhao P Zhu G Zhang W Zhang L Liang Z Zhang Y 《Analytical and bioanalytical chemistry》2009,393(1):257-261
Studies into the interactions between drugs and human serum albumin (HSA) are extremely important for drug discovery, since
HSA behaves as a carrier for external drugs and internal biological molecules. In this paper, to evaluate the pharmacokinetic
and pharmacodynamic properties of dexamethasone (DXM), the interaction between DXM and HSA was studied by capillary electrophoresis–frontal
analysis (CE-FA). According to the Klotz equation, four binding sites between DXM and HSA were obtained, and the average binding
constant was 1.05 × 103 M−1. Furthermore, according to multiple equilibrium theory, based on the assumption that there are two types of binding site,
the binding constant at one site was calculated to be 3.539 × 103 M−1, and the average of the other three was 1.234 × 103 M−1. In addition, to obtain the detailed binding information at each binding site, new equations were deduced by multivariate
regression. The four binding constants of DXM and HSA were calculated to be 5.558 × 101 M−1, 2.158 × 104 M−1, 7.312 × 103 M−1 and 2.043 × 103 M−1, respectively, which is helpful for detailed studies into the interactions between drugs and proteins with multiple binding
sites.
Figure Electropherograms of DXM sodium phosphate and HAS mixtures for different protein to drug concentration ratios, obtained by
CE-FA 相似文献
2.
The binding equilibrium between l− and human serum albumin (HSA) or bovine serum albumin (BSA) has been studied by means of the resonance Rayleigh scattering
(RRS) and equilibrium dialysis. It has been found for the first time that RRS and multiple frequency scattering (MFS) are
enhanced as the l− binding to the HSA and BSA, but fluorescence quenches. The equilibrium dialysis results suggest that the binding of l− to HSA and BSA fits a phase-distribution model other than Scatchard model, and that the order of magnitude of its phase-distribution
constant was found to be 104. It is most probable that Cl− or other anion ions influence the binding of l− by changing the ionic strength in the solution. The dialysis at different pH indicates that the binding mechanism is due
to the electrostatic forces between the l− and protonated basic amino-acid residues. 相似文献
3.
Matsuda R Anguizola J Joseph KS Hage DS 《Analytical and bioanalytical chemistry》2011,401(9):2811-2819
This study used high-performance affinity chromatography (HPAC) to examine the binding of gliclazide (i.e., a sulfonylurea
drug used to treat diabetes) with the protein human serum albumin (HSA) at various stages of modification due to glycation.
Frontal analysis conducted with small HPAC columns was first used to estimate the number of binding sites and association
equilibrium constants (K
a) for gliclazide with normal HSA and glycated HSA. Both normal and glycated HSA interacted with gliclazide according to a
two-site model, with a class of high-affinity sites (average K
a, 7.1–10 × 104 M−1) and a group of lower-affinity sites (average K
a, 5.7–8.9 × 103 M−1) at pH 7.4 and 37 °C. Competition experiments indicated that Sudlow sites I and II of HSA were both involved in these interactions,
with the K
a values for gliclazide at these sites being 1.9 × 104 and 6.0 × 104 M−1, respectively, for normal HSA. Two samples of glycated HSA had similar affinities to normal HSA for gliclazide at Sudlow
site I, but one sample had a 1.9-fold increase in affinity at this site. All three glycated HSA samples differed from normal
HSA in their affinity for gliclazide at Sudlow site II. This work illustrated how HPAC can be used to examine both the overall
binding of a drug with normal or modified proteins and the site-specific changes that can occur in these interactions as a
result of protein modification. 相似文献
4.
Yue Zhang Zi-Qiang Xu Xiao-Rong Liu Zu-De Qi Feng-Lei Jiang Yi Liu 《Journal of solution chemistry》2012,41(2):351-366
The binding of vitamin C, L-ascorbic acid (AsA), with human serum albumin (HSA) was investigated by various spectroscopic
techniques under simulated physiological conditions. The fluorescence quenching constants (K
SV) at four different temperatures (292, 298, 304, and 310 K) were obtained. The thermodynamic parameters ΔH
∘ and ΔS
∘ were calculated to be 6.02 kJ⋅mol−1 and 84.55 J⋅mol−1⋅K−1 using the van’t Hoff equation. Additional experiments to determine the stoichiometry (n) were carried out using isothermal titration calorimetry (ITC) and cyclic voltammetry (CV). The distance, r, between AsA and the tryptophan residues of HSA was calculated to be 3.7 nm according to F?rster’s non-radiation energy transfer
theory. The effect of AsA on the conformation of HSA was studied by means of three dimensional fluorescence spectra and CD
spectra. The results indicate that the presence of AsA resulted in a slight change of the HSA secondary structure. The effect
of common ions on the binding of AsA to HSA was also examined. 相似文献
5.
Fei Ding Wei Liu Xi Zhang Li-Jun Wu Li Zhang Ying Sun 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(3):1088-1094
Pyrazosulfuron-ethyl (PY) is a sulfonylurea herbicide developed by DuPont which has been widely used for weed control in cereals. The determination of PY binding affinity and binding site in human serum albumin (HSA) by spectroscopic methods is the subject of this work. From the fluorescence emission, circular dichroism and three-dimensional fluorescence results, the interaction of PY with HSA caused secondary structure changes in the protein. Fluorescence data demonstrated that the quenching of HSA fluorescence by PY was the result of the formation of HSA–PY complex at 1:1 molar ratio, a static mechanism was confirmed to lead to the fluorescence quenching. Hydrophobic probe 8-anilino-1-naphthalenesulfonic acid (ANS) displacement results show that hydrophobic patches are the major sites for PY binding on HSA. The thermodynamic parameters ΔH° and ΔS° were calculated to be ?36.32 kJ mol?1 and ?35.91 J mol?1 K?1, which illustrated van der Waals forces and hydrogen bonds interactions were the dominant intermolecular force in stabilizing the complex. Also, site marker competitive experiments showed that the binding of PY to HSA took place primarily in subdomain IIA (Sudlow's site I). What presented in this paper binding research enriches our knowledge of the interaction between sulfonylurea herbicides and the physiologically important protein HSA. 相似文献
6.
Umesha Katrahalli Seetharamappa Jaldappagari Shankara S. Kalanur 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(1):314-319
The interaction between human serum albumin (HSA) and fluoxetine hydrochloride (FLX) have been studied by using different spectroscopic techniques viz., fluorescence, UV–vis absorption, circular dichroism and FTIR under simulated physiological conditions. Fluorescence results revealed the presence of static type of quenching mechanism in the binding of FLX to HSA. The values of binding constant, K of FLX-HSA were evaluated at 289, 300 and 310 K and were found to be 1.90 × 103, 1.68 × 103 and 1.45 × 103 M?1, respectively. The number of binding sites, n was noticed to be almost equal to unity thereby indicating the presence of a single class of binding site for FLX on HSA. Based on the thermodynamic parameters, ΔH0 and ΔS0 nature of binding forces operating between HSA and FLX were proposed. Spectral results revealed the conformational changes in protein upon interaction. Displacement studies indicated the site I as the main binding site for FLX on HSA. The effect of common ions on the binding of FLX to HSA was also investigated. 相似文献
7.
Florin Bucatariu Frank Simon Gheorghe Fundueanu Ecaterina Stela Dragan 《Colloid and polymer science》2011,289(1):33-41
Synthesis of small oligopeptide brushes (oligo(S-benzyl-l-cysteine)) onto polyelectrolyte functionalized silica microparticles was developed. Poly(vinyl amine) (PVAm) adsorbed from
salt-free and KCl 10−1 mol L−1 aqueous solution onto silica microparticles was chemically and naturally cross-linked by epichlorohydrin and CO2, respectively. After the adsorption of PVAm onto microporous silica particles and stabilization by cross-linking, five repeated
coupling reactions of Boc-S-benzyl-l-cysteine were performed. To test the protein interactions with the newly designed surface, human serum albumin (HSA) has
been selected as a model protein. X-ray photoelectron spectroscopy, total organic carbon, potentiometric and polyelectrolyte
titrations, and electrokinetic analysis were employed to obtain information about the polyelectrolyte adsorption and the amount
of the amino acid S-benzyl-l-cysteine that was covalently bound to the solid surface and for determination of the protein amount adsorbed onto functionalized
surface. The amount of HSA adsorbed onto modified silica microparticles decreased in order: silica/PVAm-cross-linked (silica/PVAm-C)
(8.00 mg g−1) > silica/PVAm-C/S-benzyl-l-cysteine (6.34 mg g−1) > silica (4.86 mg g−1) > silica/PVAm-C/(S-benzyl-l-cysteine)5 (1.86 mg g−1). 相似文献
8.
de la Escosura-Muñiz A González-García MB Costa-García A 《Analytical and bioanalytical chemistry》2006,384(3):742-750
A new electroactive label has been used to monitor immunoassays in the determination of human serum albumin (HSA) using glassy-carbon
electrodes as supports for the immunological reactions. The label was a gold(I) complex, sodium aurothiomalate, which was
bound to rabbit IgG anti-human serum albumin (anti-HSA-Au). The HSA was adsorbed on the electrode surface and the immunological
reaction with gold-labelled anti-HSA was then performed for one hour by non-competitive or competitive procedures. The gold(I)
bound to the anti-HSA was electrodeposited in 0.1 mol L−1 HCl at −1.00 V for 5 min then oxidised in 0.1 mol L−1 H2SO4 solution at +1.40 V for 1 min. Silver electrodeposition at −0.14 V for 1 min followed by anodic stripping voltammetry were
then performed in aqueous 1.0 mol L−1 NH3–2.0×10−4 mol L−1 AgNO3. For both non-competitive and competitive formats, calibration plots in the ranges 5.0×10−10 to 1.0×10−8 mol L−1 and 1.0×10−10 to 1.0×10−9 mol L−1 HSA, respectively, with estimated detection limits of 1.5×10−10 mol L−1 (10 ng mL−1) and 1.0×10−10 mol L−1 (7 ng mL−1), respectively, were obtained. Levels of HSA in two healthy volunteer urine samples were also evaluated, using both immunoassay
formats. 相似文献
9.
The interaction between 18-methyl norethindrone and ketoprofen, including the displacement of ketoprofen from human serum
albumin binding sites, was investigated by the capillary electrophoresis-frontal analysis method (CE-FA) at room temperature.
A very large sample plug was introduced hydrostatically into the capillary (65 cm × 50 μm i.d.; effective length of 35 cm)
over 80 s at a height difference of 11 cm. The working conditions for CE-FA separation are as follows: operating voltage,
10 kV; running buffer, 67 mmol·L−1 phosphate, pH 7.4. The unbound ketoprofen concentration was directly measured from the height of the frontal peak. When the
concentration of 18-methyl norethindrone was increased from 0 to 200 μmol/L, the unbound ketoprofen concentration was found
to increase from 22.4 to 26.4 μmol/L at 100 μmol/L total ketoprofen concentration and from 82.1 to 106.2 μmol/L at 200 μmol/L
total ketoprofen concentration. From these data, it may be deduced that the administration of high concentration of 18-methyl
norethindrone can displace ketoprofen from its secondary binding site.
__________
Translated from Chinese Journal of Chromatography, 2005, 23(2)(in Chinese) 相似文献
10.
Martínez-Pla JJ Martínez-Gómez MA Martín-Biosca Y Sagrado S Villanueva-Camañas RM Medina-Hernández MJ 《Electrophoresis》2004,25(18-19):3176-3185
The application of the short-end capillary injection to capillary electrophoresis frontal analysis (CE-FA) to study the interaction between basic, neutral and acid drugs towards human serum albumin (HSA) at near-physiological conditions is presented. The compounds selected display a wide range of binding affinities and the results obtained were in good agreement with those reported in the literature. An equation for the estimation of the number of primary binding sites and their corresponding affinity constants is developed isolating the experimentally measured variables in just one axis. The proposed CE-FA method to screen drug interactions with HSA under physiological conditions is simple, rapid and cost-effective what may facilitate its implementation in the drug discovery process. 相似文献
11.
Summary A simple and rapid method for determination of the parameters of the interaction between drugs and protein, including the
association constant and the number of binding sites, has been developed by use of a microdialysis sampling technique combined
with high-performance liquid chromatography. The drug and protein (carbamazepine (5H-dibenz[b,f]flazepine-5-carboxamide, CBZ) and human serum albumin (HSA) were used as examples) were mixed in different molar ratios in
0.067 M potassium phosphate buffer, pH 7.4, and incubated at 37°C in a water-bath. The microdialysis probe was the used to
sample the mixed CBZ-HSA solution at a perfusion rate of 1 μL min−1. The concentration of CBZ in the microdialysate was determined by reversed-phase high-performance liquid chromatography.
Relative recovery (R), determined in vitro under similar conditions, was approximately 42.7%; theRSD ofR was approximately 1.85%. The estimated association constant (K) and the number of the binding sites,n, on one molecule of HSA were 1.06×104 M−1 and 0.880, respectively, which is in good agreement with the literature values determined by high-performance frontal analysis.
The potential use of microdialysis is also discussed. 相似文献
12.
The application of near-infrared (NIR) dyes (λ
em > 750 nm) to the analysis of biological samples shows much promise, because the long emission wavelengths of such dyes allow
interferences from biomolecule matrices to be minimized. In this paper, a novel NIR dye, 5,5′-dicarboxy-1,1′-disulfobutyl-3,3,3′,3′-tetramethylindotricarbocyanine
(DCDSTCY) has been developed for the spectrophotometric determination of total protein in serum. Under acidic conditions,
the binding of DCDSTCY to proteins caused a new peak at 878 nm, the height of which was proportional to the concentration
of protein. The linear range of the method was found to be 0.04–0.5 μg mL−1 for bovine serum albumin (BSA) and human serum albumin (HSA), and detection limits of 5 ng mL−1 were obtained for these substances. The maximum binding number of BSA with DCDSTCY was measured to be 133. The method proposed
here has been applied to the quantitation of total protein in serum, and recoveries of 96.6–104% were achieved.
Figure Near-infrared probe for protein determination 相似文献
13.
A novel method for the determination of proteins at nanogram levels was proposed based on the decrease of resonance light
scattering (RLS) signal resulting from the interaction of dibromo-o-nitrophenylfluorone (DBONPF)-sodium lauroyl glutamate
(SLG) with proteins. At pH 2.97, the decrease RLS intensity was proportional to the concentration of proteins in the range
of nanogram levels with 3σ detection limits being 3.4 ng mL−1 for bovine serum albumin (BSA), 1.7 ng mL−1 for human serum albumin (HSA), 4.1 ng mL−1 for γ-globulin (γ-IgG), 4.4 ng mL−1 for egg albumin, 6.2 ng mL−1 for pepsin (Pep) and 3.7 ng mL−1 for α-chymotrypsin (Chy). The method is no protein-to-protein variability, simple, rapid, practical and relatively free
from interference from coexisting substance, as well as much more sensitive than most of the reported methods. The proposed
method was successfully applied to determine total protein in human serum samples. 相似文献
14.
T. Anovski T. Memedović M. Rastovac 《Journal of Radioanalytical and Nuclear Chemistry》1972,12(1):483-489
Instrumental activation analysis was used to determine the contents of certain elements in human serum albumin (HSA). Sample
irradiation was performed with a thermal neutron flux of 1.5·1013 n·cm−2·sec−1 in the RA nuclear reactor of the Boris Kidrič Institute, Vinča. Measurements were performed on a 4096-channel analyser with
a high-resolution Ge(Li) detector. The Na, Cu, Br, Au, Hg, Cr, Fe, Ag, Sc, Ba and Co contents were determined in HSA produced
by the Institute for Blood Transfusion, Belgrade. 相似文献
15.
The mechanism of interaction of hypoglycemic drugs, glimepiride and glipizide with human serum albumin (HSA) has been studied
using fluorescence spectroscopy. The results are discussed in terms of the binding parameters, thermodynamics of the binding
process, nature of forces involved in the interaction, identification of drug binding site on serum albumin and the fluorescence
quenching mechanism involved. The association constants were of the order of 105 and glipizide was found to have much higher affinity for HSA than glimepiride at all temperatures. Thermodynamic parameters
for the binding suggested that hydrophobic interactions are primarily involved in the binding of these drugs to HSA. However,
glimepiride and glipizide appear to cause temperature-dependent conformational changes in the albumin molecule and, therefore,
the nature of interaction varied with temperature. Glimepiride and glipizide bind to both site I and site II on HSA, but the
primary interaction occurs at site II. The binding region in site II is different for the two drugs. Stern-Volmer analysis
of quenching data indicated that tryptophan residues of HSA are not fully accessible to the drugs and a predominantly dynamic
quenching mechanism is involved in the binding. Results can provide useful insight into prediction of competitive displacement
of these drugs by other co-administered drugs and excipients, resulting in serious fluctuations of the blood glucose levels
in diabetic patients.
相似文献
16.
Summary The dyes cibacron blue F3GA and reactive red 120 have been immobilized on acetate fiber filter rods to produce potential affinity
matrixes. The isothermal adsorption of bovine serum albumin or human serum albumin on these matrixes was investigated and
proved to conform to the Freundlich equation. In the static adsorption of human plasma the adsorption capacity for human serum
albumin was 12.5 mg g−1 fiber filter and one band was observed in SDS-PAGE electrophoresis of human serum albumin isolated by the immobilized cibacron
blue F3GA filter rod. Ligand utilization efficiencies and breakthrough volumes were obtained for adsorption of HSA on the
cibacron blue F3GA filter rod when the feed-rates were from 0.5 to 6 mL min−1. In the affinity chromatography of human plasma the yield of human serum albumin was 1.27 g per 100 mL plasma. 相似文献
17.
Wen-ying He Hui-juan Chen Fen-ling Sheng Xiao-jun Yao 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,74(2):427-433
BAFP (2,6-bis[4-(4-amino-2-trifluoromethylphenoxy)benzoyl] pyridine), a synthesized polyimide compound, was exploited for the first time to analyze its interaction with human serum albumin (HSA) by molecular modeling, fluorescence and Fourier transform infrared attenuated total reflection spectroscopy (FTIR ATR) with drug concentrations of 3.3 × 10−6 to 3.0 × 10−5 mol L−1. Molecular docking was performed to reveal the possible binding mode. The results suggested that BAFP can strongly bind to human serum albumin (HSA) and the primary binding site of BAFP is located in site II of HSA, which is supported by the results from the competitive experiment. The binding constants for the interaction of BAFP with HSA have been evaluated from relevant fluorescence data at different temperatures (296, 303, 310 and 308 K). The alterations of the protein secondary structure in the presence of BAFP in aqueous solution were quantitatively calculated by the evidences from FTIR ATR spectroscopes. The binding process was exothermic and spontaneous, as indicated by the thermodynamic analyses, and the major part of the binding energy is hydrophobic interaction, which is also in good agreement with the results of molecule modeling study. The enthalpy change ΔH0, the free energy change ΔG0 and the entropy change ΔS0 of 296 K were calculated to be −7.75, −27.68 kJ mol−1 and 67.33 J mol−1 K−1, respectively. 相似文献
18.
Protein can greatly enhance the fluorescence of curcumin (CU) in the presence of sodium dodecyl benzene sulfonate (SDBS).
Experiments indicate that under the optimum conditions, the enhanced intensity of fluorescence is proportional to the concentration
of proteins in the range of 0.0050–20.0 μg mL−1 for bovine serum albumin (BSA), 0.080–20.0 μg mL−1 for human serum albumin (HSA), and 0.040–28.0 μg mL−1 for egg albumin (EA). Their detection limits (S/N=3) are 1.4 ng mL−1, 20 ng mL−1, and 16 ng mL−1, respectively. The method has been satisfactorily used for the determination of proteins in actual samples. In comparison
with most of fluorimetric methods, this method is quick and simple, has high sensitivity and good stability. The interaction
mechanism is also studied. 相似文献
19.
《Journal of photochemistry and photobiology. A, Chemistry》2007,185(2-3):239-244
The binding of trazodone hydrochloride (TZH) to human serum albumin (HSA) was investigated by spectroscopic techniques. Various binding parameters have been evaluated. Negative enthalpy and positive entropy values indicated that both hydrogen bond and hydrophobic forces played a major role in the binding of TZH to HSA. The distance, r between donor (HSA) and acceptor (TZH) was found to be 2.16 nm based on the Förster's theory of non-radiation energy transfer. The circular dichroism data indicated that the α-helicity of HSA decreased upon interaction with TZH. The binding constant of HSA–TZH was found to decrease in presence of common ions and hence, shortened the stored time of drug in blood plasma. 相似文献
20.
Zhengjun Cheng Lei Zhang Hongmei Zhao Rong Liu Qianyong Xu 《Journal of solution chemistry》2013,42(6):1238-1262
The interactions of two drugs, cryptotanshinone (CTS) and icariin, with bovine serum albumin (BSA) and human serum albumin (HSA) have been investigated using multiple spectroscopic techniques under imitated physiological conditions. CTS and icariin can quench the fluorescence intensity of BSA/HSA by a static quenching mechanism with complex formation. The binding constants of CTS–BSA, CTS–HSA, icariin–BSA and icariin–HSA complexes were observed to be 1.67 × 104, 4.04 × 104, 4.52 × 105 and 4.20 × 105 L·mol?1, respectively at 298.15 K. The displacement experiments suggested icariin/CTS are primarily bound to tryptophan residues of the proteins within site I and site II. The thermodynamic parameters calculated on the basis of the temperature dependence of the binding constants revealed that the binding of CTS–BSA/HSA mainly depends on van der Waals interaction and hydrogen bonds, and yet the binding of icariin–HSA/BSA strongly relies on the hydrophobic interactions. The binding distances between BSA/HSA and CTS/icariin were evaluated by the Föster non-radiative energy transfer theory. The results of synchronous fluorescence, 3D fluorescence, FT-IR and CD spectra indicates that the conformations of proteins were altered with the addition of CTS or icariin. In addition, the effects of some common ions on the binding constants of CTS/icariin to proteins are also discussed. 相似文献