Serum albumin, bovine solution preparation

Protein concentration can be determined using a method introduced by Bradford,4 which utilises Pierce reagent 23200 (Piece Chemical Company, Rockford, IL, USA) in combination with an acidic Coomassie Brilliant Blue G-250 solution to absorb at 595 nm when the reagent binds to the protein. A 20 mg/1 bovine serum albumin (Piece Chemical Company, Rockford, IL, USA) solution will be used to prepare a standard calibration curve for determination of protein concentration. The sample for analysis of SCP is initially homogenised or vibrated in a sonic system to break down the cell walls. 

We used an anti-DNA antibody as an exploratory model system. The antibody was monoelonal from mouse sourees and its subelass was IgM. Mouse IgG (MW 1.5 x 10 Da) and IgM (MW 9 X 10 Da) antibodies from normal plasma, and bovine serum albumin were used for the eontrol measurements. To prevent the nonspeeilie adsorption of proteins to the uneovered, bare Au site in the modified eleetrode surfaee, the DNA-modified eleetrode prepared by the standard proeedure was further treated with aqueous 2-mercaptoethanol solution and was used for the measurements. 

Preparations of PEG-modified proteins. A. SC-PEG (1 g, 0.2 mmol) was added to a stirred solution of Bovine Serum Albumin (BSA) (100 mg, 1.5 x 10 6 mol) in 0.1 M sodium phosphate, pH 7.8 (60 mL). Sodium hydroxide (0.5 N) was used to maintain pH 7.8 for 30 min. The excess of free PEG was removed by diafiltration using 50 mM phosphate buffered saline. Approximately 30 amino groups of the native protein were modified as determined by trinitrobenzenesulfonate (TNBS) assay (28). The same degree of modification was obtained when the experiment was repeated under identical conditions using SS-PEG instead of SC-PEG. 

Fig. 3.9 SEM images of aerogels. They were prepared from initial gels synthesized by adding 10wt.% THEOS to an aqueous solution containing 1 wt.% bovine serum albumin at the various pHs shown underthe pictures. (Unpublished results obtained with the participation of N. Shipunova and D. Fomin).

The resulting product (II) is subsequently coupled to bovine-serum-albumin in a glycerol-w ater mixture in the presence of dicyclohexylcarbodiimide. The mixture is incubated overnight at 4°C, and the protein-hapten complex is dialysed against distilled water thereby causing its purification. Conjugation of the respective barbiturate to the protein carrier, comparison of the barbiturate BGG-conjugate to control BGG-solution and preparation of 14C-pentobarbital sodium are carried out respectively. 

Prepare competitor protein buffer detergent solution 4 mg/mL normal goat globulin or other competitor protein, (such as fetal calf serum, bovine serum albumin, bovine plasma, and so forth), and 0.1% saponin (Sigma, St. Louis, MO) in phosphate-buffered saline (NGG-sap-PBS). 

In order to obtain a thermodynamically stable micro emulsion, the analysis of the phase behaviour is indispensable. With bovine serum albumin instead of an enzyme (because of the cost of the bio-catalyst) phase behaviour studies are shown in Fig. 2. A strong shift of the phase boundary is observed, yielding a system that solubilises much less water in the presence of the protein. In case of hydrophobic enzymes, the addition of dry lyophilised protein to an already prepared reverse micellar solution can also work well [53]. 

Triton X-100, EDTA, dithiothreitol and electrolyte protect enzyme in dilute solution and against denaturation by heat or extreme pH-values [12, 48] <2>, at low dithioerythritol concentrations enzyme tends to aggregate [5] <2>, bovine serum albumin, 1 mg/ml, stabilizes dilute enzyme solutions [5] <2>, diadenosine pentaphosphate, i.e. AP5A, stabilizes during preparative electrophoresis [7]... 

Obtain a precast SDS-polyacrylamide slab gel or prepare one according to instructions in Experiment 4. The recommended gel is 12°/o acrylamide with a thickness of 0.75 mm. Protein samples are prepared as follows Purified proteins (transferrin, bovine serum albumin, a, -antitrypsin, a-lactalbumin from Experiment 4, and molecular weight standards) are supplied in Tris buffer, pH 6.8 solutions at a concentration of 1 mg/mL. Sera samples have been diluted and are ready for use. Prepare protein samples for electrophoresis in 0.5-mL microcentrifuge tubes with attached caps. Label the tubes from 1 to 5 as below or per your Instructor s directions. 

Microcystin-LR (MC-LR) (Sigma, France) standard solutions first prepared in 50 50 methanokwater and subsequently diluted in 30 mM tris-HCl, 2mM dithiothreitol (DTT), 2mM ethylene diamine tetraacetic acid (EDTA), 0.2mgmL 1 bovine serum albumin (BSA), 20 mM MgCl2 buffer (pH 8.4) (prepared in Milli-Q water). 

The effects of conditioning layers of two important blood serum proteins, albumin and fibrinogen were investigated. Protein adsorption was studied using bovine serum albumin (BSA) and fibrinogen (F) from Sigma. The samples were incubated for 3 h at 37°C in solutions of albumin (1 mg/mL) and fibrinogen (0.2 mg/mL) prepared in phosphate buffered saline (PBS, 0.01 M phosphate buffer, 0.0027 M KC1, 0.137 MNaCl, pH 7.4). After the incubation period, the samples were rinsed 3 times with PBS and analyzed by the various surface characterization techniques. 

A solution of bovine serum albumin (BSA) was prepared by mixing 0.5 ml of a stock solution with 9.5 ml of water. Given that the extinction coefficient for BSA at 280 nm is 0.667 (mg/ml)-1 cm-1 and the concentration of BSA in the stock solution was 2.0 mg/ml, predict what absorbance would result from this solution at 280 nm. You may assume that a 1-cm-pathlength cuvette was used. 

Protein molecular weight standards—Suggested standards are phosphorylase (97,400 Da), bovine serum albumin (66,200 Da), ovalbumin (45,000 Da), carbonic anhydrase (31,000 Da), soybean trypsin inhibitor (21,500 Da) and lysozyme (14,400 Da) at 1 mg/ml each in a single mixture in 0.01 M Tris chloride buffer, pH 7.0 (prepared by dilution of the stock 1 M buffer above). Approximately 2 ml of this solution will be required. 

Standard curve A series of dilutions of bovine serum albumin in water are prepared containing between 0 and 100 pig protein in 1 ml volume and the assay is performed as described above on each dilution. The exact concentration of the bovine serum albumin stock solution is determined using the molar absorption coefficient of 45 000 for bovine serum albumin at 279 nm after diluting to approximately 0.2 mg/ml. 

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