For bovine serum albumin

Compare the two methods in terms of the assumptions involved, the supple mentary information required, and the sensitivity to experimental error 11. The following values of n/c2 versus C2 were measuredf at 25°C in 0.15 NaCl solutions for bovine serum albumin ... 

The observed fluorescence blue shift following BLG adsorption was, however, small compared with the one observed for bovine serum albumin [28]. Univariate analysis... 

This blend is recommended as thin-gel composite membranes for bovine serum albumin ultra-filtration [114],... 

Fig. 44. LS plots142) for bovine serum albumin in iso-ionic salt free aqueous solution [plot (b)]. Also shown are data (open circles) for solution in 0.001 M NaCl [plot (c). Plot (a) is for same data as in (b) plotted against the square root of the bovine serum albumin concentration, c2, according to Eq. (94)...

Cell Culture-Derived Media-Derived Protein Impurities. Immunoassays can detect low impurity levels (<1 ppm).4 The ELISA is probably one of the most sensitive analytical methods. If bovine serum is used as a media component, then testing should include ELISAs for bovine serum albumin (BSA), bovine transferrin, bovine fetuin, and bovine IgG. Often hormones and growth factors, such as insulin or insulinlike growth factor, are used as media components. ELISAs should be used to detect and quantitate these residuals in the various production steps as well as in the final product. There are commercially available antibodies to most commonly used media components. If proprietary media components are used, then the same investment in time and effort is required for the production of specific antibodies, as described above for host cell impurities. 

EXAMPLE 3.5 Evaluation of Charges of Macroions from Osmotic Pressures. In Example 3.3, we evaluated M and B for bovine serum albumin at pH = 5.37, at which the molecule is known to be uncharged. Use the data in Figure 3.6 to evaluate B and, from it, the charge of the molecule at pH = 7.00. The data in Figure 3.6 were measured in 0.15 M NaCI. 

Except for bovine serum albumin, immunoglobulins, and fat globule membrane proteins, the nomenclature employed in this classification consists of the use of a Greek letter, with or without a numerical sub-... 

Bovine serum albumin is denatured at pH 4 because of repulsion of acidic amino acids (Haurowitz 1963). As with a-lactalbumin, failure to measure the heat of denaturation for bovine serum albumin at pH 3 indicates that it is already unfolded by acid (de Wit and Klarenbeek 1984). It is more stable at pH 7.5 than at pH 6 because of increased activity of thiol groups at high pH. Denaturation is enhanced more by calcium ions than by other anions (Shimada and Matsushita 1981). Fatty acids appear to stabilize bovine serum albumin against heat denaturation (Gumpen et al 1979). 

Comparison of equilibrium adsorption (Figures 4 and 5) and minute protein adsorption/flocculation as a function of protein concentration, Cp, demonstrates strong but variable effects of pH and salinity.4 The equilibrium adsorption of proteins is as large as 1 mg/m2 (or 300 mg/g) at pH 3.5 (i.e. between pH(IEP) of silica and proteins) for bovine serum albumin (BSA) with 0.9 wt.% NaCl and gelatin without NaCl, or at pH(IEP) of protein for ovalbumin without NaCl. The lowest equilibrium adsorption (0.1-0.2 mg/m2) is typically observed at pH = 2, which is close to pH(IEPS o2) 2.2, and without NaCl (Figure 4). It should be... 

Figure 1. SDS-PAGG analysis of alkaline-dissolved Bacillus thuringiensis subspecies kurstaki (BTK) and israelensis (BTI) -endotoxin at 25 yg per track (1) BTK -endotoxin from Biochem Products - US Division (Salsbury Labs., Inc.), (2) BTI 6-endotoxin from Sandoz Inc., (3) BTI (Sandoz) -endotoxin purified by DEAE-anion exchange chromatography, (4) percipitate formed after dialysis of BTI (Sandoz) -endotoxin into pH 4.5 sodium acetate buffer, (5) soluble fraction after dialysis of BTI (Sandoz) -endotoxin into pH 4.5 sodium acetate buffer, (6) BTI (Sandoz) -endotoxin purified by Sephadex G-75 gel filtration chromatography at Rf 1.35, (7) at Rf 1.58, and (8) BTI strain IFC-1 -endotoxin from Biochem Products - US Division (Salsbury Labs., Inc.). S, molecular weights as indicated X1000 for bovine serum albumin (BSA), ovalbumin (OA), trypsin, and myoglobin. Reproduced with permission from Ref. 29. Copyright 1984, Academic Press, Inc.

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. 

Fig. 4. Calibration curve obtained for bovine serum albumin (BSA), by monitoring amount of urease-BSA conjugate bound to anti-BSA antibody. Data were obtained with tubes containing 1.5 ml of BSA standard, 40 fil of 1 100 anti-BSA serum, 40 /al of 1 10 urease-BSA conjugate, and 300 1 of insolubilized goat anti-rabbit y-globulin suspension, all prepared in 10 mAf Tris-HCl-EDTA, pH 7.5.

Fig. 46. Sum S(t) and difference D(t) curves for Bovine Serum Albumin labeled with DNS in aqueous solution at pH 7.2 S(t) - upper curve, Dlt) - hiver curve. Points are experimental data,...

Fig. 11. Chart of retention times for bovine serum albumin (BSA) and turkey serum albumin (TSA), which have been proteolitically treated with pepsin. For pH values 7.0-5.0, peaks 1 and 2 represent the albumin dimer and the proteolitically nicked monomer, respectively, at different pHs (N form). At pH 4.0 there is an abrupt dissociation of the two halves of albumin to yield peaks 1 and 2, which represent the intact monomer (incomplete digestion, F form) and the two equal molecular weight halves of albumin, respectively. (D. C. Carter, P. D. Twigg, and K. Keeling, unpublished results).

Figure 11. Experimental osmotic coefficient data (X) [41, 112] for bovine serum albumin (BSA) and the corresponding multicomponent model results (full line) at pH = 5.4. For pH = 7.3, experimental data are denoted by (+) and one-component model results by the dashed line.

Measured and Calculated Times for Bovine Serum Albumin Films To Reach 0.1 mN m-1 at a Fresh Interface0,11... 

Figure 3 A series of CZE electropherograms for bovine serum albumin (BSA), anti-BSA, and complexes of BSA-anti-BSA. Operating conditions uncoated capillary, 50 pm X 70 cm, 40 cm to detector, 15 kV applied voltage, UV detection at 214 nm, vacuum injection 30 kpa-s, buffer 60 mM phosphate, pH 7.8,1 M AccuPure Zl-methyl reagent (Waters), sample dissolved in phosphate buffer, pH 7.0. (a) Injection of anti-BSA purified on protein G column first, (b) Injection of BSA, monomer purified by SEC first, (c) Mixture of BSA monomer and anti-BSA, with anti-BSA in excess, (d) Mixture of BSA monomer and anti-BSA, with BSA in excess (peak assignments peak 1 = 1 1 complex peak 2 = 1 2 complex, other peaks as indicated) (59).

Ji, L. et al., Al-MCM-41 sorbents for bovine serum albumin Relation between Al content and performance, Micropor. Mesopor. Mater., 75, 221, 2004. 

For experiments with proteins, this theory, together with data for osmotic pressure, also aids in explaining the rather unusual response of ultrafiltration rate to pressure and the virtual Independence of this response from fiber length and axial flow velocity. Osmotic pressure data are available in the literature for bovine serum albumin at pH 7.4 ( ), and osmotic pressure measurements of moderate accuracy were made by the authors on bovine calf serum. 

Graphs of tt vs. time are plotted for various positions of the blade (distance X) compressing over the same area. Figure 1 represents a family of curves for bovine serum albumin. Curve fitting of these results leads to... 

One of the limitations on the use of sc carbon dioxide as a reaction medium has been the difficulty of getting substances dissolved or finely dispersed in it. Johnston and coworkers have overcome this difficulty for bovine serum albumin by making a microemulsion of water in carbon dioxide using the fluorinated surfactant (8.3).192... 

Lignophenols having a linear structure were obtained by the surface reaction of a native lignin and phenols in sulfuric acid. Laccase catalyzed the oxidative polymerization of lignocatechol in a mixture of ethanol and phosphate buffer to give the crosslinked polymer [92]. The product showed high affinity for bovine serum albumin and glucoamylase. 

Fig. 8.5 Affinity-electrophoresis patterns for bovine serum albumin (BSA) on gels containing an immobilized derivative of stearic acid (A/-acrylyl-6-amidocaproic acid N-octadecylamide). The electrophoreses were carried out at 25 C under a pressure of 1.8 kbar at a constant current of 1 mA per tube. The total acrylamide concentration was T = 6 per cent (C = 3.44 per cent). The ligand concentration (in (xm) in the gels was (1) 0, (2) 0.90, (3) 1.81, (4) 3.62, and (5) 5.43 (adapted from work by Masson and Reybaud). ...

Fig. 8.8 Polyacrylamide-gel electrophoresis of the tetrameric form (G4) of human butyrylcholinesterase in microcapillary gel tubes with different gel concentrations, T. Gel patterns for electrophoresis at 2 kbar and 20°C for (a) butyrylcholinesterase, and (b) butyrylcholinesterase in the presence of 2 m sorbitol (the gels were stained for enzyme activity according to the procedure of Karnovsky and Roots ). The numbers indicate the acrylamide concentrations T. (c) Ferguson plots constructed for butyrylcholinesterase at different pressures (o), atmospheric pressure, ( ) 0.5 kbar, ( ) 1 kbar, (A) 1.5 kbar, and ( ) 2 kbar. (d) A secondary plot of /Cr against pressure for ( ) bovine serum albumin, ( ) butyryicholinesterase, and ( ) butyrylchoiinesterase in the presence of 2 m sorbitol, (e) A secondary plot of log Vo against pressure for butyrylchoiinesterase.

Figure 7.12 Flux-pressure relationship for bovine-serum albumin solutions in a stirred batch cell at various stirring rates and protein concentrations.101...

Using this method, we constructed a number of dynamic adsorption isotherms for several proteins on different surfaces. Here we present information for two proteins. The adsorption isotherm for bovine serum albumin (BSA) (87% monomer, 13% dimer described by the supplier as 100% monomer) is shown in Figure 6. A plateau concentration for BSA on an amine/ silane surface was 3.5 mg/m2, which is comparable with monolayer adsorption reported previously in a static system (3). [The effect of flow rate, ionic strength, and temperature is reported elsewhere (18).] Perhaps more interesting are the data for plasma fibronectin (produced and purified extensively in our laboratory), because adsorption characteristics of this protein have not been reported elsewhere. Since it is a protein intimately involved in cellular adhesion, its surface behavior is particularly relevant to implant biocompatibility. We found a plateau uptake of approximately 7.0 mg/m2 on both amine and dimethyldimethoxymethylsilane, and based on the assumption of monolayer coverage and a published axial ratio (20), we calculated that the molecule has dimensions of approximately 130 X 80 X 100 A. 

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