Adsorption immobile

The assumption of the association of Hb in the pores of carboxylic cation exchangers has been advanced in Ref. [47] on the basis of electron microscopy at the maximum filling, almost all the pore surface is filled with Hb associates which are ordered star-shaped structures. Interprotein interaction in the adsorption immobilization of enzymes have been reported in Refs. [74, 75]. 

It is interesting to note that many crystal poisons not only interfer with nucleation and the growth of crystals but may also retard their dissolution. As we have seen (Chapter 6), precipitation and dissolution of solids proceed by the attachment or detachment of ions most favorably at kink sites of the crystalline surface. Solutes such as organic substances, or phosphates may upon adsorption immobilize kinks and thus retard dissolution. 

Lasagna uses electro-osmosis to mobilize contaminants into installed in situ treatment zones where contaminants are removed by adsorption, immobilization, or degradation. The technology is currently undergoing field demonstrations and is not yet commercially available. It will be marketed by Envirogen, a subsidiary of Monsanto Company. 

Balfanz, J. Rehm, H-J. (1991). Biodegradation of 4-chlorophenol by adsorptive immobilized Alcaligenes sp. A 7-2 in soil. Applied Microbiology and Biotechnology, 35,662-8. 

Certain orientations may make a specific site on the protein inaccessible to ligand, substrate, or antigen. For example, consider the adsorptive immobilization of a specific IgG for a solid-phase immunoassay. The procedure will be optimal if the Fab domains are free to bind antigen (Figs. 1 and 16). 

Immobilization of the amplicon on GEC electrode. Add 20 nL of amplicon solution in 10 x SSC (containing 3 pmol of the amplicon approximately) to the surface of the electrodes, as shown in Fig. 30.1(vi) and perform the dry-adsorption immobilization at 80°C for 45 min.Wash briefly with 5 x SSC solution, eliminating adsorbed salts [3]. 

An adsorptive immobilization is a non-covalent coupling method on solid supports that is based on electrostatic, Van der Waals interactions, hydrogen bonds, and hydrophobic interactions of the reactants. 

On an Au/ITO electrode, Hb exhibited similar electrochemical behavior to Mb if Hb was immobilized on the electrode surface by casting the Hb solution thereon. However, when Hb was immobilized on Au/ITO by adsorption of Hb on a modified electrode, no direct voltammetric response for Hb could be seen. This was because the adsorption of Hb on the modified electrode did not provide a sufficient amount of protein. However, the adsorptive immobilization of Hb on a gold nanoparticle-modified ITO electrode could be observed by electrochemical impedance measurements using an [Fe(CN)6]37[Fe(CN)6]4 redox probe (Figure 14) [46], By the simulation program, the charge transfer resistance (Rt) value of bare ITO is estimated to be 77.43 kQ, which is decreased to 15.97 kQ after the gold nanoparticles... 

The electrochemical and electrocatalytic properties of carbon electrodes can be modified changing their surface composition by anchoring foreign compounds. This can be accomplished by adsorption, by chemical reaction with a surface group, by specific chemical binding, and by adsorption immobilization on a sublayer of a polymer material [40]. Chemically modified electrodes constitute a part of supramolecular chemistry. 

Since the adsorption of a protein to a surface is basically a reversible process, changes of pH, ionic strength, substrate concentration, temperature, etc. may detach the biomolecule from the carrier (Carr and Bowers, 1980). In addition to the simplicity of the procedure, the advantage of adsorptive immobilization is that it does not need nonphysiologi-cal coupling conditions or chemicals potentially impairing enzyme or cell functions. An activity loss is therefore seldom observed. 

Since nonspecific adsorption is regarded as a major source of systematic error in heterogeneous immunoassays, the adsorptive immobilization of different Ab solutions was studied on clean, nonaminated glass surfaces (Fig. 

In general, adsorption immobilization is an extremely easy process as the resin is simply mixed with the enzyme in aqueous buffer and gently stirred/shaken, typically over night, followed by filtering and drying. However, a potential problem with the method is leaching of the enzyme from the support in the application. This limits the number of reuses and enzyme contamination in the reaction... 

Table 8.5 Examples of sensors using adsorption immobilization. 

Thermal stabilities of CALB immobilized on coconut fiber were investigated at 50 and 60 °C, and results were compared to the stability of soluble CALB and Novozyme 435 (Fig. 5 and Table 2). It can be observed, by analyzing stabilization factors F) on Table 2, that immobilization of CALB on coconut fiber promoted an improvement on thermal stabilities, as CALB-7A is 2- and 92-fold more stable than soluble CALB at 50 and 60 °C, respectively. Other authors [19] obtained similar results when immobilizing the same enzyme on activated carbon by adsorption immobilized CALB was 2-fold more stable than soluble enzyme with ti/2=8 h to thermal stability studies at 50 °C. 

In a typical application for immunosensing, the emission of fluorescein-labelled antibody bound to a hapten-protein conjugate adsorptively immobilized on a quartz plate in contact... 

The next step for the improvement of the kinetics of this reaction is made possible through adsorptional immobilization of hydrogenase. In the case of adsorption on soot of hydrogenase from T. roseopersicina, up to 90% of the activity of the native enzyme is preserved. Figure 16 shows the enzymatic and... 

Electrode surface modification has been done by different DNA adsorption immobilization procedures, electrostatic adsorption or evaporation, with the formation of a monolayer or a multilayer DNA film. A very important factor for the optimal construction of a DNA-electrochemical biosensor is the immobilization of the DNA probe on the electrode surface [2-6]. 

Finally, let us notify that the first order of dependence of polymerization rate upon initiation rate at the adsorptive immobilization on the surface of filler of polymeric initiator can also be explained by the essential contribution of reactive diffusion to chain termination, i.e., supplying the reactive centers of macroradicals to one another at the expense of their propagation [18]. 

Adsorption immobilization of the reagent in chemooptical interface was utilized in fiber optic chemical sensors i.e. pH sensor, redox titrator and calcium sensitive optrode. The choice of the indicator as well as the support and the immobilization procedure governs the working and dynamic ranges of the pH sensor. The optrode based on optimized redox optomembrane consisting of PETP additionally covered with PVC) may be used in various redox titrations e.g. Fe(II) with MnfVII) or As(HI) with Cr(VI). Hardness of water can be measured by the fiber optic calcium sensor directly in the studied medium without any sample preparation. 

Open tubular capillary microreactor Trypsin Adsorption Immobilized metal-ion chelating capillary microreactor Trypsin immobilized on chelator silane reagent reacted onto the capillary wall [134]... 

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