Denaturing agent

Each interference type may require a different elimination strategy, the simplest of which is to remove the potential interference before beginning the assay. Removal is commonly done in manual analysis, usually by deproteini2ation, eg, by addition of some denaturing agent such as trichloroacetic acid. 

A principal use of 2-propanol is to make acetone, a solvent, and as a starting mater - m making other organic compounds. Smaller amounts of 2-propanol are convened to other cheii Is or used as a solvent, rubbing alcohol, or denaturing agent for ethyl alcohol. 

FIGURE 8.6 Comparison of hexafluoro-2-propanol (HFIP) with formic acid as a denaturing agent in SEC. Eiution positions of neutral amino acids were similar with both agents. The elution positions of Lys and Asp shifted dramatically in C, as shown by the tie lines, but this was an effect of pH (see Fig. 8.7). The elution positions of a-MSH and formic acid are shown to demonstrate that the amino acids eluted within Vo and V,. Column Same as Fig. 8.1. Flow rate 1.0 ml/min. Mobile phase As noted. Detection Aiij = 0.1 AUFS. 

Guner A. and Kara M. Cloud points and temperatures of aqueous poly(N-vinyl-2-pyrrolidone) solutions in the presence of denaturing agents. Polymer 39, 8 9, 1569-1572,1998. 

Fixation is denaturation changing the shape of tissue molecules. This is accomplished in a variety of ways by different denaturing agents and the resultant shapes differ markedly, but the consequences are much the same endogenous and microbial enzymes can no longer attack the tissue (it is preserved), and the structure of tissue molecules is stabilized. Whether we like what we see from this depends upon what we want to see and what we are used to seeing. 

Other fixatives and denaturing agents cause shape changes but do not actually attach to tissue molecules. Some remove water in various ways. Others change the environment, causing molecules to twist about to lower their overall energy (molecules always go to their lowest possible energy state). 

Immobilized enzymes have been found in a considerable number of cases to be markedly more stable to denaturation by heat, denaturing agents, or organic solvents, than the corresponding native enzymes (6). The reasons for this effect are still not fully understood, and it is thus recommended that in the future a thorough analysis be carried out of the conformation, ease of denaturation, and conformational fluctuations of immobilized enzymes. 

The delipidated serum lipoprotein proteins exhibit solubility differences in aqueous media. The polypeptides of HDL and the D polypeptides of VLDL are readily soluble in aqueous media, particularly in slightly alkaline low-ionic strength buffers (S28, S30). In contrast, the LDL protein does not dissolve in such buffers and, like many other water-insoluble proteins, requires denaturing agents, detergents, or suitable chemical modification. The many techniques for the solubilization of apo LDL have been reviewed recently (G15). A thorough assessment of such techniques is not possible since not all the solubilized products have been characterized. The choice of the method presently depends on the investigator s preference and experimental needs. 

Biophysical studies have shown that many denatured proteins can spontaneously refold in vitro, upon removal of a denaturing agent (urea, detergent, acid, and so on). Certain enzymes and other proteins can accelerate the folding process in vitro, and it has been concluded that their role in vivo is to prevent misfolding or aggregation. However, these protein factors serve more to facilitate the folding process than to specify a particular spatial shape for the product. 

The aim is to extract protein molecules as pure as possible. Detergents generally help membrane proteins to dissolve and separate from lipids. Reductants are used to reduce disulfide bonds or prevent oxidation. Denaturing agents alter ionic strength... 

Gradient former for two solutions with different concentrations of a denaturing agent, with a volume of 15 - 20 ml for each solution. The gradient former should be positioned approximately 50 cm over the workplace. 

Denaturing agents substances added to alcohol to render it unfit for use as an intoxicating beverage. 

The lack of higher structures probably explains the high stability of the caseins to denaturing agents, including heat. 

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