Solid phase immobilization

Fig. 8 Symmetrical chiral salen ligands used in solid phase immobilization...

Fig. 7. Principle of the solid-phase immobilized epitope immunoassay (SPIE-IA).

Fig. 9. Schematic representation of the noncompetitive immunoassay of triiodothyronine using a solid-phase immobilized hapten for masking an unoccupied antibody.

Yamanaka SA, Charych DH, Loy DA, Sasaki DY. Solid phase immobilization of optically responsive liposomes in sol-gel materials for chemical and biological sensing. Langmuir 1997 13 5049-5053. 

For immobilized lipase preparations, a more complex mechanism is expected to occur since esterification efficiency is also highly dependent on the hydration state of the enzyme preparation, which can be greatly modified by the nature of the substrate and the support (1,4)- In the case of butyl butyrate synthesis, analysis of substrate polarity measured as partition coefficient (Table 1) showed a higher value for butanol than for butyric acid, favoring butanol migration to the solid phase (immobilized lipase). Thus, there should be more alcohol than acid at the active site of the immobilized lipase, requiring an excess of acid in the reaction medium to provide equimolar amounts of reactants and satisfactory yields (7). 

After completion of each esterification reaction, the medium was centrifuged, and the solid phase (immobilized enzyme) was recovered according to the method described by Langone and Sant Anna (11). Then, the experiments were performed reusing the enzyme recovered after eachbatch reaction assay. 

Multiphase system — An inhomogeneous system consists of two or more phases of one or more substances. In electrochemistry, where all processes occur at the interface thus all measurement systems must contain at least two - phases. In common understanding so-called multi-phase systems contain more than two phases. Good examples of such systems are -> electrode contacting a solid phase (immobilized at the electrode electroactive material or heterogeneous -> amalgams) and electrolyte solution, and an electrode that remains in contact with two immiscible liquids [i]. All phenomena appearing in such multi-phase systems are usually more complicated and additional effects as - interphase formation and -> mass transport often combined with - ion transfer must be taken into account [ii]. 

Enzyme-Labeled Antigen. In this method, the sample is first incubated with a moderate excess of solid-phase immobilized antibody (Ab ). After washing, excess enzyme-labeled antigen (Ag ) is allowed to bind to unreacted Ab . 

Assays for insulin antibodies fall into three categories (1) quantitative radioimmunoelectrophoresis, which measures the binding of IgG antibody to radiolabeled insulin by rocket Immunoelectrophoresis into anti-IgG-containing agarose (2) RIAs with separation of bound and free insulin by precipitation with PEG or a second antibody and (3) solid phase immobilization of insulin to test tubes or Sepharose. These are discussed in more detail in Reeves. ... 

Effects of solid-phase immobilization on the activity or inhibition of the enzyme... 

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