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Films albumin

Figure 5. Albumin adsorption isotherms on Silastic before and after fat removal from the albumin. Films were equilibrated at 37°C for 20 hrs at the depicted albumin concentration in O.OIM HEPES, 0.147M NaCl, 0.02% azide, pH 7.4 and then rinsed with buffer at room temperature by the dilution displacement technique. Fraction V albumin (NBC 2106) was used untreated or defatted with charcoal (see Table III... Figure 5. Albumin adsorption isotherms on Silastic before and after fat removal from the albumin. Films were equilibrated at 37°C for 20 hrs at the depicted albumin concentration in O.OIM HEPES, 0.147M NaCl, 0.02% azide, pH 7.4 and then rinsed with buffer at room temperature by the dilution displacement technique. Fraction V albumin (NBC 2106) was used untreated or defatted with charcoal (see Table III...
In native state, proteins exist as either fibrous or globular form. Protein should be denatured and unfolded to produce an extended chain structure to form film. Extended protein chains can interact through hydrogen, ionic, and hydrophobic bonds to form a three-dimensional stmcture (24). Protein films are excellent gas barriers but poor moisture barriers because of their hydrophilic nature. Mechanical properties and gas permeability depend on the relative humidity (1). Al-ameri (25) smdied the antioxidant and mechanical properties of soy, whey and wheat protein, and carrageenan and carboxymethyl cellulose films with incorporated tertiary-butylhy-droquinone (TBHQ), butylated hydroxytoluene (BHT), fenugreek, and rosemary extracts. Armitage et al. (26) studied egg albumin film as a carrier of natural antioxidants to reduce lipid oxidation in cooked and uncooked poultry. [Pg.3350]

Measured and Calculated Times for Bovine Serum Albumin Films To Reach 0.1 mN m-1 at a Fresh Interface0,11... [Pg.287]

Biswas B, Haydon DA. The effect of certain small molecules on the elasticity of adsorbed serum albumin films. Kolloid Z Z Polymere 1962 186 57-61. [Pg.438]

When the albumin films are adsorbed to the surface of the peu-425, the formation of a protein film is evident. Some substructure is seen at the 270/sec and 540/sec shear rates. However, the most striking observation is that the hard segment model peu-ppd, which would be expected to adsorb proteins the most readily, adsorbs albumin in a fashion similar to the polystyrene surfaces. The albumin adsorbs to the peu-ppd as distinct molecules at the low flow rates, and at the 270/sec rate the formation of a network is evident. [Pg.60]

Albumin. After albumin as adsorbed onto a germanium ATR crystal (from a saline solution), the adsorbed film was then exposed to pure saline followed by either methanol or ethylene glycol (13,14). After subtraction of the solvent, the spectrum of the adsorbed albumin film exposed to saline was compared to the spectrum of the adsorbed albumin film exposed to either of the non-aqueous solvents. Three major differences were observed in the films exposed to a non-aqueous solvent ... [Pg.354]

Figure 10 (left). Infrared spectra of albumin in the Amide III spectral region. Top Albumin dissolved in saline at pH 8.8. Bottom Adsorbed albumin film exposed to saline at pH 8.8. (Reproduced with permission from Ref. 13. Copyright 1986 Wiley.)... [Pg.359]

Kolivoska, V., Gal, M., Hromadova, M., Lachmanova, S., Tarabkova, H., Janda, P., Pospisil, L., Turonovd, A.M. Bovine serum albumin film as a template for controlled nanopancake and nanobubble formation In situ atomic force microscopy and nanolithography study. Colloids Surf. B Biointerfaces 94, 213-219 (2012)... [Pg.286]

Figure 9 Creep curve of an adsorbed bovine serum albumin film (pH = 5.2) at a petroleum etheiywater interface, at a constant stress of 0.0116 Nm . [Pg.111]

It would appear from Table II that the protein films pack to e8sen> tially the same area at the point of minimum compressibility, the average value for the 9 proteins in Table II being 0.78 M /mg. The compressibility of the film, however, varies considerably and the same protein can show quite different values depending on the substrate. For example, the minimum compressibility of egg albumin film on a dilute acetate buffer is 0.028 while on 35% (NH4)2S04 it is 0.010. Bateman and Chambers (38) investigated the elasticity of spread e albumin films as a function of the pH of the substrate. In their first paper they concluded that the film elasticity was practically independent of pH, while in their second paper they report that the film elasticity exhibits a pronounced maximum at the isoelectric point. The infiuence of pH on the compressibility of spread films is obscure. [Pg.110]

In general, as a protein film is compressed the potential difference AF increases. Examination of equation 6 shows that this increase could be due to increasing number of molecules per unit area, to a decrease in 6, i.e., to an orientation of the dipoles normal to the surface, or to a decrease of D. It is commonly assumed that D remains constant as the film is compressed (20). If D actually remains constant as the film is compressed, then the potential difference should be a function only of n and the angle of tilt, n can be calculated from the area of the film and any variation in AF/n should be a function only of cos 0. For gliadin films, for serum albumin films, for j3-IactoglobuIin films and for... [Pg.111]

The question as to why, in the case of bovine albumin films, the amount of adsorbed antibodies increases with the number of underlying monolayers is of importance. First, it seems probable that the antibody molecules are piled up on top of each other in the thick layers of antibodies adsorbed on four double layers of bovine albumin. If this is true, the same process might take place in other cases. It has often been reported that undiluted immune sera gave much thicker layers of specifically adsorbed material than diluted sera. Bateman, Calkins and Chambers (19) found increments in thickness of 200 A and 60 A with undiluted and diluted serum, respectively. These variations have usually been assumed to result from a different orientation of the adsorbed antibody molecule which in the case of the rabbit antibody has approximately the dimensions of 40 X 270 A. Great variations in the thickness of adsorbed layers of antibodies have also been observed by electron microscopy. For instance, Anderson and Stanley (24) reported an adsorbed thickness of 225 A of rabbit antibodies on the surface of tobacco mosaic virus molecules but they also have observed much smaller increments. [Pg.133]

Figure 15.7 gives a typical creep curve for bovine serum albumin films, showing an initial, instantaneous, deformation, characteristic of an elastic body, followed by a non-linear flow that gradually declines and approaches the steady flow behaviour of a viscous body. [Pg.612]

After 30 minutes, when the external force was withdrawn, the film tended to revert to its original state, with an instantaneous recovery followed by a slow one. The original state, however, was not obtained even after 20 h and the film seemed to have undergone some flow. This behaviour illustrates the viscoelastic property of the bovine serum albumin film. [Pg.612]

A nice article that describes the importance of oxygen diffusion for silicone-based soft contact lenses may be found online http //www.clspectrum.com/article.aspx7article=12953 Note if the lens contains a hydrophobic surface, it will disrupt the tear flow that results in the deposition of an albumin film on the lens. Not only will this reduce the effectiveness of the lens to correct optical aberrations, but will also cause infection/irritation. Eor more details regarding the lens surface and eye complications, see Rao, J. B., Saini, J. S. Complications of Content Lenses in Contact Lenses. Aquavella, J. V., Rao, G. N., eds. Lippincott Williams and Wilkins Philadelphia, PA, 1987. [Pg.452]

Tearings reqnire relative movements of the molecnles, and the intrinsic viscosity of the snrface layers, viscosity which makes these movements difficult, also obstructs those which lead to tearings as well as those which bring interior molecules in the increased interstices of the external ones. Thus, while passing from soap to albumin, the tension, i.e. the force which tends to tear the films, becomes double, but the resistance to this tearing increases at the same time by the increase in the viscosity of the surface layers, and the albumin films extend in bnbbles like those of soap, only to a lesser degree. [Pg.222]


See other pages where Films albumin is mentioned: [Pg.30]    [Pg.30]    [Pg.261]    [Pg.276]    [Pg.309]    [Pg.108]    [Pg.983]    [Pg.18]    [Pg.19]    [Pg.86]    [Pg.70]    [Pg.103]    [Pg.130]    [Pg.130]    [Pg.135]   
See also in sourсe #XX -- [ Pg.130 , Pg.132 , Pg.135 ]




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