Ultrafine iron oxide nanoparticles were prepared in aqueous solution using chemical coprecipitation method. Adsorption of bovine serum albumin (BSA) on magnetic particles was studied in the presence of silane coupling KH550. Characterizations of magnetic particles were carried out by X-ray diffraction, Transmission electron microscopy, Fourier transform infrared spectrometer and vibrating-sample magnetometer. The experimental results showed that magnetic nanoparticles were well dispersed with a small decrease of the magnetic saturation after modification. Magnetic nanoparticles wrapped in KH550 were favorable to the adsorption of BSA while the capability of hydrophile increased consequently, which could be used for target carrier in biomedicine.
Animals ; Cattle ; Ferrosoferric Oxide ; chemistry ; Magnetics ; Metal Nanoparticles ; chemistry ; Serum Albumin, Bovine ; chemistry

Beta-Elemene is an antitumor drug which is isolated from the traditional Chinese medicinal herb Curcumae Phaeocaulis Rhizoma, it is the main component of elemene which is extracted from the plant and delivered via blood circulation after intravenous injection. The antitumor effect of beta-elemene in vitro and in vivo was definite, and beta-elemene could improve the patient immunity and no sever side effect, drug resistance or bone marrow suppression were found during the clinical studies. And human serum albumin (HSA) is a primary extracellular protein which has a high concentration distribution in blood plasma and has many characteristic physiological functions. Therefore, the binding of beta-elemene to protein may be very important for absorption, distribution, metabolism and elimination. Therefore, the study on the interaction of beta-elemene with drug-carrying protein is very important. In this work, molecular binding of beta-elemene to human serum albumin (HSA) was investigated by using spectrofluorometer. the binding constants suggested that a strong interaction and the formation of a complex between beta-elemene and HSA. This clearly implies that beta-elemene can be stored and removed by the proteins in the body. Furthermore, the fluorescence quenching results showed that the HSA fluorescence was quenched by beta-elemene through static quenching mechanism. Thermodynamic parameters showed that hydrophobic interactions play a role in the binding of beta-elemene to HSA. The negative deltaH(0) and positive deltaS(0) in case of beta-elemene therefore showed that electrostatic attraction play a role in the binding of beta-elemene to HSA.
Drugs, Chinese Herbal ; chemistry ; Humans ; Kinetics ; Protein Binding ; Serum Albumin ; chemistry ; Sesquiterpenes ; chemistry ; Spectrometry, Fluorescence ; Thermodynamics

Cell adhesion to material surface plays an important role in regulating cell function such as proliferation and differentiation. Surface patterning provides a useful method to control cell spatial distribution and adhesion to substance. Here microcontact printing and microfluidic channels were introduced to pattern MC3T3 E1 osteoblasts on silicon substance. Dichlordimethylsilane (DMS) was used in microcontact printing to generate the alternating domains of DMS and non-DMS, and cells preferentially adhered to the non-DMS and hydrophilic region. On the patterned surfaces generated from collagen and albumin solutions with microfluidic channels, cells preferentially localized in the collagen-coated region. The results also showed that micropatterning could be a useful method to study the effect of surface chemistry on cell adhesion and other functions.
Cell Adhesion ; Cells, Cultured ; Collagen ; chemistry ; Dimethylpolysiloxanes ; chemistry ; Osteoblasts ; physiology ; Serum Albumin, Bovine ; chemistry ; Surface Properties

In this paper, the new carbon nanotube modified glassy carbon electrode (F-CNTs/GCE) was prepared to establish a new method for studying the molecular interaction mechanism between baicalin metal complexes (BMC) and bovine serum album (BSA), and the principle of this method was discussed deeply. Under the physiological condition, the thermodynamics and kinetics properties of interaction between BMC and BSA were studied by cyclic voltammetry (CV) to inference their molecular effective mechanism. The results show that the presence of F-CNTs can accelerate the electron transfer, and better response signal was showed in the BMC/BMC-BSA system. The detection of interaction of BMC-BSA used new method show that BMC-BSA generates stable thermodynamically non-covalent compounds, and the obtained average binding sites of BMC-BSA were 1.7; the number of electron transfer in BMC/BMC-BSA reaction process was 2, and non electroactive supramolecular compounds of BMC-BSA were generated by this interacting reaction. The relevant research work provides a new way to study the molecular mechanism for the interaction of drugs with protein, and with a certain reference value for discussion on the non covalent interactions.
Animals ; Cattle ; Coordination Complexes ; chemistry ; Electrodes ; Flavonoids ; chemistry ; Kinetics ; Nanotubes, Carbon ; Serum Albumin, Bovine ; chemistry ; Thermodynamics

OBJECTIVE: To explore the interaction between cefdinir (CE) and bovine serum albumin (BSA) by fluorescence and ultraviolet-visible absorption spectrometry.
 METHODS: Under the optimal conditions, the interaction between CE and BSA was investigated by fluorescence and ultraviolet-visible absorption spectrometry.
 RESULTS: CE could quench (static quenching) the intrinsic fluorescence of BSA by forming the CE-BSA complex. The main binding forces were considered as hydrogen bonds and Van der Waals forces based on the calculated values of the thermodynamic parameter. The process of binding was spontaneous because Gibbs free energy change was negative. The primary binding site for CE was located at sub-domain II of BSA. The values of Hill's coefficients were less than 1, indicating a negative cooperative effect. Synchronous fluorescence spectra showed that the conjugation reaction between CE and BSA did not affect the conformation of BSA, and the binding site was close to the tyrosine residue.
 CONCLUSION This test provides a theoretical basis for revealing the pharmacokinetic issue and the development for new drugs.
Binding Sites ; Cefdinir ; Cephalosporins ; chemistry ; Serum Albumin, Bovine ; chemistry ; Spectrophotometry, Ultraviolet ; Thermodynamics

AIMTo propose a new simple and sensitive voltammetric method for determination of proteins.

METHODSProtein with sulfhydryl or disulfide bond in 0.5 mol x L(-1) NaOH, 1.5 x 10(-4) mol x L(-1) Pb2+ and 0.02% tetrabutylammonium iodide was heated in boiling water for 5 minutes. The reactive product gave a well defined reductive adsorption wave at -0.66 V (vs SCE) by means of single sweep polarography, and the height of derivative wave was proportional to the concentration of proteins.

RESULTSThe peak height was linearly proportional to bovine serum albumin (BSA) or human serum albumin (HSA) concentration in range of 7.5 x 10(-10) -3.0 x 10(-7) mol x L(-1) (r(BSA) = 0.9995, and r(HSA) = 0.9990). The detection limit of BSA or HSA was 3.0 x 10(-10) mol x L(-1). For lysozyme (Lyso), the concentration range was from 1.4 x 10(-8) to 1.3 x 10(-6) mol x L(-10 (r(Lyso) = 0.9997) and the detection limit was 7.0 x 10(-9) mol x L(-1).

CONCLUSIONThe method is simple, rapid, sensitive and applicable to the assay of diluted human serum albumin samples.

Adsorption ; Animals ; Humans ; Lead ; Muramidase ; analysis ; Polarography ; methods ; Quaternary Ammonium Compounds ; Serum Albumin ; analysis ; chemistry ; Serum Albumin, Bovine ; analysis ; chemistry ; Sodium Hydroxide

In the present paper, the influence of carbon phase components of three kinds of diamond like carbon (DLC) films, viz. DLC, DLC rich in graphite and DLC rich in diamond films, on adsorption of human serum albumin (HSA), human serum fibrinogen (HFG) and immunoglobin (IgG) was quantitatively analyzed by use of T-type correlation degree in the grey system theory. Through the analysis, the rational explanation for adsorptive amounts variations of the serum proteins with phase components in the experiment is reached and some essential conclusions have been obtained: (1) The effect of graphite phase and C-H phase on HSA adsorption are greater than that of other phase components; with the increase of these two phase coumponents, the adsorptive amounts of HSA decrease; (2) The powerful influence on HFG adsorption stems from DLC phase and C-O phase; with the decrease of DLC phase or the increase of C-O phase, the adsorptive amounts of HFG increase; (3) All of the carbon phase components have only limited influence on IgG adsorption in positive or negative fashion with a little difference in degree; (4) DLC phase has both effects of enhancing adsorption for HSA and weakening adsorption for HFG and IgG, thus its influence on the hemocompatibility of DLC films is much more important than that of other phase components.
Adsorption ; Carbon ; chemistry ; Coated Materials, Biocompatible ; chemistry ; Diamond ; chemistry ; Humans ; Materials Testing ; Membranes, Artificial ; Serum Albumin ; chemistry ; Surface Properties

OBJECTIVETo study the conjugation reaction characteristics of caffeic acid micromolecule cistanoside F and bovine serum albumin.

METHODThe interaction between bovine serum albumin (BSA) and cistanoside F that was separated from Callicarpa plant for the first time and abbreviated CF was detected by fluorescence (FS), UV-vis absorbance and circular dichroism (CD) under simulative physiological conditions.

RESULTCF-BSA's static apparent binding constant (K(a)), number of binding sites (n), efficiency of energy transfer (E), spatial distance (r), thermodynamic parameters deltaG, deltaH and deltaS and changes in alpha-helical structure content in BSA before and after CF's effect were calculated to define the binding site of CF in BSA and analyze the impact of several common metal ions on the interaction of CF and BSA.

CONCLUSIONGround state compounds formed by CF and BSA could cause intrinsic fluorescence quenching. Their binding constant K(a) of cistanoside F with BSA was 4.36 x 10(4) L x mol at 25 degrees C, the number of binding site n was 1, and the spatial distance r was 3.09 nm. The results indicated that the hydrogen bond played a major role in cistanoside F-BSA association. The displacement experiments confirmed that cistanoside F can bind to site I of BSA. In addition, the binding constant of cistanoside F with BSA was enhanced after the addition of some common metal ions Mg2+, Fe3+, Cu2+ and Zn2+. The intrinsic fluorescence of BSA was quenched by cistanoside F via forming cistanoside F-BSA complex and non-radiation energy transfer. CD spectra showed that the binding of cistanoside F with BSA induced conformational changes in BSA.

Animals ; Caffeic Acids ; chemistry ; Catechols ; chemistry ; Cattle ; Circular Dichroism ; Glycosides ; chemistry ; Serum Albumin, Bovine ; chemistry ; Spectrometry, Fluorescence ; Spectrophotometry, Ultraviolet ; Thermodynamics

The evaluation of the adsorption of methylene blue (MB) in plasma by sulfonated polyethersulfone (SPES) adsorbent column was carried out in this study. The results indicated the adsorption of MB by SPES adsorbent column was more efficient than that by polyethersulfone (PES). In addition, the changes of the concentration of BSA solution passing through adsorbent column along with the time and the biochemical indices of plasma before and after adsorption treatment were also investigated. The results showed that the adsorption amount of BSA by PES adsorbent column was larger than that by SPES, and the biochemical parameters such as total protein, albumin, glucose, triglyceride and total cholesterol in plasma varied slightly before and after passing through the column, which were still within the clinical indices.
Adsorption ; Humans ; Methylene Blue ; isolation & purification ; Plasma ; chemistry ; Polymers ; chemical synthesis ; chemistry ; Serum Albumin, Bovine ; chemistry ; Sulfones ; chemical synthesis ; chemistry

OBJECTIVETo establish a direct and fast method separating calcium levofolinate and calcium dextrofolinate in a bovine serum albumin stationary phase chiral column.

METHODSUsing EC150/4 RESOLVOSIL BSA-7(150 mm x 4 mm) chiral separation column, with 0.20 mol/L, pH=5.0 phosphate buffer as mobile phase HPLC method was performed to separate calcium folinate enantiomers.

RESULTThe capacity factor and resolution of the two calcium folinate enantiomers were greatly affected by mobile phase buffer concentration,pH and the column temperature. And the retention time of calcium levofolinate and calcium dextrofolinate were 18.5 min and 22.6 min, respectively. The resolution, R(s)=1.49.

CONCLUSIONCalcium folinate enantiomers are separated successfully using this method.

Chromatography, High Pressure Liquid ; Hydrogen-Ion Concentration ; Leucovorin ; chemistry ; metabolism ; Serum Albumin, Bovine ; metabolism ; Stereoisomerism