Immobilization of Target Molecules

Collioud, A., Clemence, J.-F., Sanger, M., and Sigrist, H. (1993) Oriented and covalent immobilization of target molecules to solid supports Synthesis and application of a light-activatable and thiol-reactive cross-linking reagent. Bioconjugate Chem. 4, 528-536. 

The final performance of the immobilized NA probes in the hybrid capture of target molecules (sensitivity and discrimination) is strongly dependent upon a number of parameters related to the immobilization process. These include (i) the chemical and physical properties of the surface, since they can influence nonspecific binding of target and nontarget (in mixtures) molecules (ii) the distance between the immobihzed NA probes and the solid surface and the orientation of the immobilized probe (iii) the density of the... 

Antibodies are commonly used for the capture of target molecules on the waveguides and they are immobilized by either physical adsorption or through a self-assembly monolayer (SAM). In the former situation. 

Second, we tried the immobilization of DNA molecules as a potential target material for the immobilization of biological macromolecules. An aqueous solution of 1 mg/mL A.-DNA was spotted onto the surface of an azopolymer and covered with a cover glass, where the A.-DNA was stained with a fluorophore (YOYO-1 iodide, Molecular Probes Inc., Eugene, OR) in advance and the surface was then irradiated with the linearly shaped laser beam for 5 min, as shown in Fig. 3b. The surface was washed for 5 min in an aqueous solution and was then observed using... 

The ultimate goal of this project is to design enzyme-based PL PSi detectors for toxic chemical detection therefore, the selection of enzymes active towards these types of target molecules is critical. Table I shows activity parameters of some enzymes in solution that have hydrolysis activity toward G-type nerve agents. OPAA-2 was selected for immobilization because it has relatively high activity towards GB and GD, as well as towards surrogates such as DFP, and /7-nitro-phenyl-soman (20-23). The products from the enzymatic action would be a phosphonic acid and HF. 

Affinity (AC) Covalently immobilized affinity lig d on particles Aqueous buffers Good choice for capture of target molecule at low concentrations in sample... 

An enhancement of SPR signal intensity was observed by the addition of the antibody to the divalent antigen-antibody complex immobilized onto the surface of the sensor chip, indicating the formation of linear supramolecules. An amplification method of the detection signals for a target molecule has been... 

A variation on the theme of conventional assay uses both lanthanide-labeled and biotin-labeled single strands to form split probes for sequence of target strands (Figure 12).120 When both of these bind to DNA, the complex binds (via the biotin residue) to a surface functionalized with streptavidin, immobilizing the europium and allowing assay to be carried out. This approach is already very sensitive to DNA sequence, since both sequences must match to permit immobilization of the lanthanide, but can be made even more sensitive by using PCR (the polymerase chain reaction) to enhance the concentration of DNA strands. In this way, initial concentrations corresponding to as few as four million molecules can be detected. This compares very favorably with radioimmunoassay detection limits. 

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