Dynamic affinity

Dye wastewater, 9 431 Dynamic affinity chromatography, 6 398 Dynamic allotropy, 23 564 Dynamically formed membranes, 15 813t Dynamic coefficient, 15 205 Dynamic compressors, in refrigeration systems, 21 535... 

O. Miyawaki and T. Yano, Dynamic affinity between dissociable coenzyme and immobilized enzyme in an affinity chromatographic reactor with single enzyme, Biotechnol. Bioeng., 39, 314-319 (1992). 

It has been shown by a stability analysis71 that the measure of relative affinities in a displacement separation is the dynamic affinity of a species which is given by... 

Thus, a plot of log K vs v (dynamic affinity plot) defines two regions demarcated by a line with slope log(A) and intercept log(A). The line originates at the point A on the ordinate axis and passes through the point defined by the parameters K and v of the species. The region above the affinity line includes all solutes which will displace the solute when traveling at a velocity characterized by A. Conversely, the solutes in the region below the affinity line will be displaced by the solute under these conditions. 

A dynamic affinity plot is presented in Fig. 10 for the proteins bovine and horse heart cytochrome c on a cation-exchange column. As one moves in a counterclockwise direction, the dynamic affinity of the molecule increases. The dynamic affinity plot provides an easy method of determining the order of elution in a displacement experiment as is shown in Fig. 4B. 

FIGURE 10 Dynamic affinity plot for cytochrome c s from bovine and horse heart and BAEE under the condition described in Fig. 4B. (Kundu et al.4i)... 

While the dynamic affinity plot provides a simple graphical representation of the order of elution in a displacement, that order is restricted to the particular operating conditions chosen for that experiment (i.e., for a specified value of A). In contrast, the affinity ranking plot can show the variation of the dynamic affinity of a molecule over a range of A values. To enable this comparison, the dynamic affinity A (which is the criterion for displacement) can be plotted against the displacer partition ratio A (which is the operating variable for displacement). The equation for such a plot can be determined by rearrangement of Eq. (6) as... 

For a given A value, the higher the A value, the better the displacer under those operating conditions. As expected, an increase in the A value as one moves along the x axis (which corresponds to lower displacer concentrations or lower salt concentrations) results in a decrease in the value of the dynamic affinity (A). This plot has been employed to rank the relative efficacy of displacers51,54 and to provide insight into the important structural features of low molecular weight displacers (Section VII). 

Obviously, quantities hot and hi are always symbate to the respective chemical potentials and P . It is important that the difference between the logarithms of rushes fij and hj be proportional to the current thermo dynamic affinity A j of the reaction between reaction groups i and j—in other words, to the thermodynamic force Xy related to flux... 

In Fig. 31, the dependences of D on the value A6= 6 6j are adduced, which characterizes as the first approximation the solvent thermo-dynamical affinity in respect to polymer [16]. As it follows from this figure data, certain laws are observed for these parameters relation. At first, A6 increase or solvent thermo-dynamical affinity in respect to polyaner change for the worse in all cases results in increase or macromolecular coil compactness enhancement, that is defined by the Eq. (8) within the framework of fractal analysis. Thus, the larger A5, is the smaller macromolecular coil gyration radius is at the same polymer molecular weight MM (or polymerization degree N). 

According to the SMA model, the characteristic charge and the affinity constant together determine the affinity of a given solute in ion exchange chromatography, rather than the affinity constant alone as it was assumed in the conventional approaches. A dynamic affinity parameter, X, can be defined as follows ... 

The sensitivity of the dynamic affinity, X, to changes in the operating conditions is given by the following equation ... 

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