Conjugates labels,

Scorilas, A., Bjartell, A., Lilja, H., Moller, C., and Diamandis, E.R (2000) Streptavidin-polyvinylamine conjugates labeled with a europium chelate Applications in immunoassay, immunohistochemistry, and microarrays. Clin. Chem. 46, 1450-1455. 

Wilbur, D.S. (1992) Radiohalogenation of proteins An overview of radionuclides, labeling methods, and reagents for conjugate labeling. Bioconjugate Chem. 3, 433-470. 

The binding of the antigen and antibody can be affected by several factors, including the conjugated label chosen for detection and the method used to conjugate the label, as well as the assay format itself. The selectivity of the ELISA can be affected by the assay format. In an ELISA with a two-site sandwich format, independent epitopes are bound by different antibodies.26 The specificity comes from multiple site recognition. Polyclonal antibodies can react with many epitopes on a complex antigen surface.24... 

As shown in Fig. 21, in a direct ELISA the unlabeled antigen (a range of standard antigen concentrations or unknown samples) is attached to the solid phase. Enzyme-conjugated (labeled) primary antibody is then added. After incubation and washing of the plate... 

Methods based on chemiluminescent and bioluminescent labels are another area of nonisotopic immunoassays that continue to undergo active research. Most common approaches in this category are the competitive binding chemiluminescence immunoassays and the immunochemiluminometric assays. Chemiluminescence and heterogenous chemiluminescence immunoassays have been the subject of excellent reviews (91, 92). Detection in chemiluminescence immunoassays is based on either the direct monitoring of conjugated labels, such as luminol or acridinium ester, or the enzyme-mediated formation of luminescent products. Preparation of various derivatives of acridinium esters has been reported (93, 94), whereas a variety of enzyme labels including firefly or bacterial luciferase (70), horseradish peroxidase (86, 98), and alkaline phosphatase are commercially available. 

Key Words Antibody alkaline phosphatase conjugation labeling glutaraldehyde. 

Key Words Antibody horseradish peroxidase conjugation labeling periodate oxidation. 

Key Words Antibody fluorescein rhodamine conjugation labeling. 

Vaidyanathan G, Affleck D, Welsh P, et al. (2000). Radioiodination and astatination of octreotide by conjugation labeling. Nucl. Med. Biol. 27 329-337. 

Fig. 21. In vivo diagnostic application of hyaluronic acid immobilized gold nanoprobes. (A) The fluorescence quenching by nanoparticle surface-energy transfer between Hilyte-647 dye labelled oUgo-HA and gold nanocluster (left) is followed by fluorescence recovery after addition of reactive oxygen species/HAdase which release the dye labeled oUgo-HA fragments. (B) Tail vein injection of GNPs capped with HA conjugates labelled with Hilyte-647 in normal (up) and arthritis (bottom) mice. Adapted from Ref 103. (See Color Plate 43.)...

As already mentioned, these acyclic BFCs have favorable labeling kinetics for most metals, but they often lack kinetic stability. In fact, DTPA coupled via one of the five carboxylic acid functions is not suitable for any other radionuclide than In because of its in vivo instability (Harrison et al. 1991). Attempts to use DTPA-peptide conjugates labeled with for therapy... 

In general, there are two different strategies to combine a biomolecule with a chelator-metal complex the pre-conjugation and the post-conjugation labeling approach. 

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