Biospecific binding

Porous glass (PG) modified with covalently adsorbed poly(p-nitrophenyl acrylate), as described in Sect. 4.1, turned out to be a highly suitable carrier for immobilization of various biospecific ligands and enzymes. When the residual active ester groups of the carrier were blocked by ethanolamine, the immobilized ligands when bound to the solid support via hydrophilic and flexible poly(2-hydroxyethyl acrylamide). The effective biospecific binding provided by the ligands... 

Biospecific adsorption, 6 396-397, 399 Biospecific binding, in microarray fabrication, 16 385 Biospecific elution, in affinity chromatography, 6 398 Biosphere, selenium occurrence in, 22 78. 

The method was confirmed experimentally with sucrose hydrolysis catalyzed by invertase, that had been immobilized by biospecific binding on concanavalin A-bead cellulose. Figure 6B shows good agreement between the substrate concentration determined by the conversion of thermometric signals of Fig. 6A and those obtained by spectrophotometric analysis. From the data shown in Fig. 6B, the initial rate was determined to be v0 = 0.775 mM min1. Introducing this value into Eq. (23), vobs was calculated and the value of the transformation parameter a was determined from Eq. (24). 

Fig. 6. Investigation of kinetic properties of immobilized invertase by flow microcalorimetry in the circulation mode. Initial sucrose concentration 51 mM, invertase immobilization by biospecific binding on concanavalin A-bead cellulose was prepared by binding on concana-valin A linked to chlorotriazine-activated cellulose, a Raw experimental thermometric data b data after conversion by the procedure indicated in Fig. 4. Concentrations were determined spectrophotometrically (open symbols) and by transformation of thermometric data explained in Section 5 (closed symbols) [32]...

Immunoaffinity separations are widely recognized as having potential to demonstrate more selectivity than any other condensed-phase separation technique [33-35]. These separations are based on biospecific binding interactions between an antibody, often chemically bound to an immobilized support, and a target molecule or antigen in the sample. See Fig. 2 for a representation of this interaction. 

The distribution of bonded molecules is a very important parameter for bioaffinity sorbents. Evidently, biospecific binding is dramatically dependent not only on the spatial disposition of bonded affinity ligands, but even on the number of ligand-surface bonds (one - or more) [41]. 

In a more recent approach, the streaming potential in a miniature column containing immobilized biosorbent has been evaluated (Matti-asson, 1984 Glad et al., 1986). The interaction between the sorbent and the analyte could be indicated via the change of the charge distribution within the electrical double layer caused by the biospecific binding. Carbohydrates have been determined with this sensor system by using con A. 

Fig. 11 1 Schematic representation of the esterification reaction involved in biotinylation of the surface in the poly(thiophene-co-3-thiophenemethanol) copolymer inverse opal. 2 The biotinylated copolymer surface is then primed for 3 biospecific binding with avidin [114]...

Ligand-binding. The biospecific binding interaction between an analyte and a biological macromolecule, usually a protein. Such an interaction is non-covalent, usually reversible and either crucial for biological activity, or can be exploited for analytical purposes. 

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