Binding isotherm poly

In the binding isotherm model [55], a polyion labeled P has N fixed charges. The poly ion is divided into sections [55]. There is no section of the polyion that has more than one binding site. Let the counterion valence be zc. Let. 1 denote a specific configuration of the nc counterions. In this configuration, the counterions bind to the poly ion and form the complex Dj(nc), and are described by the equilibrium [55]... 

FIG. 12 Binding isotherms of proteins to poly(styrenesulfonate) under its sodium form. Open symbols pH 7.5, ionic strength 0.1 M closed symbols pH 6.7, ionic strength 0.05 M. Bovine serum albumin (A, A) /3-lactoglobulin ( , O). v is the mol/ mol ratio of bound protein per sulfonate. (Reprinted with permission from Ref. 78. Copyright 1998 American Chemical Society.)... 

FIG. 13 Log-log plot of the binding isotherms of amphiphilic proteins to amphiphilic poly anions. ( , o) /3-lactoglobulin to copolymer of maleic acid and octyl- or dodecyl vinylether, respectively pH 8.7 and ionic strength 0.1 M (data from Ref. 50). (0, , A) bovine serum albumin to C18 modified poly(acrylic acid), pH 9.0 in 30 mM NaOH-boric acid buffer. Modification rate 10, 3, and 1 mol% respectively (data from Ref. 63). Free protein in /rniol/L protein/polymer ratio in number of protein globules per 1000 monomers. 

Dubin et al. used capillary electrophoresis to separate the complexes of proteins with synthetic polyanions from the free protein in the complex solution and to determine the complex composition. The binding isotherms were studied in relation to the pH value [70], the chain length of the poly-... 

Figure 13.3. Calculated and observed binding isotherm of sodium decyl sulfate for poly(L-...

Free DDA concentration (x10 ) M Figure 10.2 Binding isotherms of DDA with native (1) and denatured (2) DNA, with single-stranded polyribonucleotides poly (U) (3), poly(A) (5), as well as with double helix poly(U) poly(A) (4). (From Ref. [10].)... 

In the initial studies carried out to date, poly-s tyrene-supported dimethylamine polymers crosslinked with 2 and 15% divinylbenzene (DVB) were complexed with m-chlorobenzoic acid and the adsorption isotherms defined. The corresponding binding constants were calculated to be 126.19 and 67.99 m", respectively. It is thus evident that the polymer support affects the strength of the binding interaction between the ligand and substrate. Mechanistic studies to understand the basis for this influence and its use in the design of polymers for selective molecular complexation reactions are in progress. 

Weickenmeier and Wenz [84] investigated the inclusion complex formation of poly[(N-vinyl-2-pyrrolidone)-co-(maleic acid)] modified with j8-CD moieties with 1-adamantanamine and with 1-adamantanecarboxylic acid by isothermal titration calorimetry. They reported 1 1 inclusion complexes between -CD moieties and adamantane derivatives with relatively large binding constants (ca. 3-5 x 10 M ). 

Fig. 10. Isothermal titration calorimetry of the binding of Sac7d to DNA at 80° showing the heat flow (A) following a series of 10 n,l injections of Sac7d (0.55 mAf) into poly(dG-dC) poly(dG-dC) (0.34 mM) in 10 mAf KH2PO4 (pH 6.8) and 25 xnM KCl. The baseline has been flattened by subtraction of a polynomial fit of the raw data. A fit of the integrated heats per mole of injected protein (B) with the McGhee-von Hippel model is shown with the solid curve through the data (A( = 1.04 x lO W", site size = 4.2 base pairs, A/f° = —52.5 kcal/mol). The first two points are inaccurate because of diffusion from the injection needle during equilibration and were not included in the fit.

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