Solubilizers chemical properties

The information available in this polypeptide or these polyeptides is far from definitive. Controversy exists on size and molecular weight of the apo LDL monomers, their number, and chemical properties (Table 8). Also, the question of polypeptide heterogeneity has not been resolved this is not surprising in view of the difficulty of protein solubilization discussed earlier. At the time of this writing, apo LDL is the mostly poorly characterized protein of all serum lipoproteins. This apoprotein is... 

Physical / chemical properties affect the rate of biodegradation mostly by affecting bioavailability. Compounds which are sparingly soluble in water tend to be more resistant to biodegradation, possibly due to an inability to reach the microbial enzyme site, a reduced rate of availability due to solubilization, or sequestration due to adsorption or trapping in inert material (Alexander, 1973 Alexander, 1994). 

The very complex variation of the amount solubilized, as well as physico-chemical properties, with chemical structure of solubilizate and surfactant as well as with surfactant concentration cannot be adequately discussed solely in terms of the energetical conditions of the solubilizate in the micelles. Thus one should also consider the conditions in the phase which separates out at the solubilization limit this is in most cases a liquid crystalline phase. A fundamental basis for a proper understanding of solubilization in surfactant systems is, therefore, a detailed information on phase equilibria in three-component systems surfactant-solubilizate-water. Due in particular... 

Knowledge of the physical and chemical properties as well as the cellular location of the target protein helps in designing the separation process. Whether the protein is intra- or extracellular, soluble or insoluble in the cytoplasm, bound to the cell membrane or located within the organelles, will affect the selection of the separation method and the type of buffering system. Proteins bound to the cell membrane require detergents or organic solvents for their solubilization. 

Further development of reliable, high-loading soluble supports with complementary solubilizing properties and with high stability to organic reaction conditions can be expected. An intriguing tme combinatorial approach to the optimization of the physico-chemical properties of soluble supports has recently been reported by Gravert et al. (287) and is described in Section 11.3.2. 

Surface active agent. A chemical compound, which when dissolved or dispersed in a liquid, is absorbed at an interface giving rise to a number of important chemical properties. The compound includes in its molecule one group that has an affinity for polar surfaces, ensuring solubilization in water, and a group that has little affinity for water. 

The role of micelles in practical systems derives from (i) their competition with monomers in adsorption processes, (ii) their use as a reservoir of monomers, (iii) their ability to solubilize materials and affect their physical and chemical properties, and (iv) their usefulness as model systems. 

Chemical properties of solvents, like the physical properties, are very important. Solubility parameters or the solvency factors provides an idea of how good a solvent is to solubilize certain types of materials. Polarity, acid-base properties, hydrogen bonding ability, and water miscibility are important chemical properties of solvents and are somewhat related. 

The solubility of an organic compound in a micelle depends on the surfactant structure and chemical properties, micelle geometry, ionic strength and composition, temperature, and solute structure and properties. Almgren M.A. et al. (1979) and Jafvert C.T. (1991) have shown that for hydrophobic compounds solubilized within micelles, a Poisson distribution is obeyed that is the solubilization of one molecule does not affect the solubilization of another. Solubilization of compounds generally is initiated at the cmc and is proportional to the surfactant concentration beyond this point. Kile D.E. and Chiou... 

Over 50 methods have been employed in the literature to determine CMC values of bile salt solutions (reviewed in [6]). These can be divided into two broad categories (a) methods requiring no physical or chemical additive in the bulk solution and (b) methods involving the use of an additive in the bulk solution. The former methods, also called non-invasive, include surface tension and the measurements of a variety of colligative bulk properties (conductivity, turbidimetry, osmometry, self-diffusion, refractive index, modal volumes, electrometric force) or electromagnetic bulk properties (NMR, sound velocity and adsorption, etc.), all as functions of bile salt concentration. The second set of methods, also called invasive, depends upon a change in some physical or chemical property of an additive which occurs with the formation of micelles. These include the spectral change of a water-soluble dye, micellar solubilization of a water-insoluble dye, interfacial tension at liquid-liquid interfaces, and partition coefficients between aqueous and immiscible non-polar phases. Whereas a detailed discussion of the merits and demerits of both approaches can be found elsewhere [6], non-invasive methods which are correctly utilized provide the most reliable CMC values. 

DeLuca PP, La dim an L and Schroeder HG, Physical chemical properties of substituted amides in aqueous solution and evaluation of their potential use as solubilizing agents, /. Pharm. 

As Rowland (8) points out there are a number of reasons for modifying cellulose, including "(a) to solubilize it for regeneration into fiber and films, (b) to make it thermoplastic for moldings and extrusions and soluble for coatings, (c) to modify its bulk properties without change in physical form, and (d) to modify its chemical properties."... 

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