Search results for " Albumin"
showing 10 items of 320 documents
Action de la chlorhexidine sur l'expression de la virulence de
1999
Abstract Candida albicans is an opportunistic yeast. Its pathogenicity is linked to the susceptibility of the host surface as well as to particular factors of the strain: adhesion, filamentous growth and secretion of proteolytic enzymes. Chlorhexidine digluconate is an antiseptic with fungicidal properties. The action of the antiseptic on the growth of the yeast shows a minimal inhibitory concentration (MIC) at 50 μg·mL−1 and a minimal fungicidal concentration (MFC) at 100 μg·mL−1. The consequences of antiseptic treatment are studied using two indicators of pathogenicity: filamentation and the secretion of acid proteinase. Concerning the morphological indicator, a complete inhibition of fil…
Joint Aqueous Solutions of Dextran and Bovine Serum Albumin: Coexistence of Three Liquid Phases
2014
The phase diagram of the system water/dextran (DEX)/BSA was measured as well as modeled. On the experimental side, cloud points were determined and the coexisting phases were analyzed. The theoretical calculations use an approach capable of describing solutions of chain polymers and of globular proteins with the same formalism. The required thermodynamic input comes from experiments concerning the binary subsystems, except for the polymer blend for which one interaction parameter had to be adjusted. Both sources of information yield the same essential features: the existence of a large composition area of immiscibility, starting from the subsystem DEX/BSA and extending well into the region …
Liquid/Gas and Liquid/Liquid Phase Equilibria of the System Water/Bovine Serum Albumin
2013
The thermodynamic behavior of the system H2O/BSA was studied at 25 °C within the entire composition range: vapor pressure measurements via head space sampling gas chromatography demonstrate that the attainment of equilibria takes more than one week. A miscibility gap was detected via turbidity and the coexisting phases were analyzed. At 6 °C the two phase region extends from ca. 34 to 40 wt % BSA; it shrinks upon heating. The polymer rich phase is locally ordered, as can be seen under the optical microscope using crossed polarizers. The Flory-Huggins theory turns out to be inappropriate for the modeling of experimental results. A phenomenological expression is employed which uses three adju…
Selective extraction of small proteins from biological samples using a novel restricted access column with cation exchange properties
2000
The determination of proteins utilising a polymer-based restricted access suppor material with ion exchange properties (IERAM) is outlined. Solid phase extraction coupled on-line with a mincrobore reversed phase HPLC system for the quantitation of small marker proteins is demonstrated. The cation-exchange restricted access packings were characterised with respect to their adsorption and desorption kinetics. The IERAM material was also investigated by capacity, selectivity, and biocompatibility determinations when applied to the quantification of small molecular weight proteins such as cytochrome C, Lysozyme, Ribonuclease A, Myoglobin, Insulin, human serum albumin, and a Tryptic inhibitor.
Optimisation of fast protein separations on non-porous silica-based strong anion exchangers
1993
The adsorbed coating technology using various vinylpyrrolidone-vinylimidazole copolymer compositions was carried out on 1.7 μm non-porous monodisperse silica. It was shown that the retention properties and the loading capacity for bovine serum albumin (BSA) increases with the amount of vinylimidazole in the copolymer composition. The retention behavior of various proteins as a function of the salt composition in the eluent has been applied to find the optimal conditions for the synthesis of the anion-exchange stationary phase. The suitability of these supports for the fast separation of biological molecules is demonstrated. The best resolution and the highest speed in protein analysis was o…
Effects of protein on retention of ADH enzyme activity encapsulated in trehalose matrices by spray drying
2008
The retention of the enzymatic activity of alcohol dehydrogenase (ADH) on spray drying was examined under various drying conditions. Trehalose was used in the formulation of feed stocks for the spray drying. The retention of ADH activity was dependent on the concentration of ADH in the feed solution. The addition of other proteins, such as bovine serum albumin and β-lactoglobulin, exhibited an additional improvement of the retention of ADH activity. The inlet and outlet temperature of the drying air was another key factor for the enzyme activity on the spray drying. The surface morphology of the spray-dried particle was changed drastically with the addition of proteins.
Synthetic Antitumor Vaccines Through Coupling of Mucin Glycopeptide Antigens to Proteins
2017
The requirements for coupling reactions of carbohydrate molecules very much depend upon the biological recognition processes that should be investigated and upon the target structures of the desired carbohydrate ligand. If the carbohydrate conjugate itself is the recognized ligand, as for example, the binding site of a P-selectin ligand comprising sialyl-LewisX and a specific peptide sequence, the natural glycoside bond must be installed. A stereoselective and regioselective block glycosylation between a sialyl-LewisX trichloroacetimidate and a partially deprotected Thomsen–Friedenreich antigen derivative was developed to achieve this aim. In contrast, the coupling reactions by which glycop…
Competing salt effects on phase behavior of protein solutions: tailoring of protein interaction by the binding of multivalent ions and charge screeni…
2014
The phase behavior of protein solutions is affected by additives such as crowder molecules or salts. In particular, upon addition of multivalent counterions, a reentrant condensation can occur; i.e., protein solutions are stable for low and high multivalent ion concentrations but aggregating at intermediate salt concentrations. The addition of monovalent ions shifts the phase boundaries to higher multivalent ion concentrations. This effect is found to be reflected in the protein interactions, as accessed via small-angle X-ray scattering. Two simulation schemes (a Monte Carlo sampling of the counterion binding configurations using the detailed protein structure and an analytical coarse-grain…
Thermodynamics and Kinetics of the Interactions Between Proteins and Hydrophilic Polymers
2021
Hydrophilic polymers are being investigated as possible coating agents for therapeutic nanoparticles because of their capacity to reduce immune response and increase circulation life time. The mechanism of action of these coatings is not well understood although it is clear that they unspecifically reduce the amount of proteins adsorbing on the nanoparticle surface coming in contact with biological fluids. Here we have investigated, using state-of-the-art atomistic molecular dynamics simulations, the equilibrium and kinetic properties of the interactions forming between human serum albumin, the most abundant protein in the blood stream, and two different and promising polymers poly(ethylene…
Polymer Complexes in Biological Applications
2013
This chapter summarizes the influence of polyelectrolyte topology on biological functions and biomedical applications such as cell uptake, drug delivery, and gene transfection. Polyelectrolytes utilized are spherical structures derived from dendrimers and albumin or cylindrical brushes, all of which are decorated with various polypeptide chains.