Sequential competitive assays

Sequential competitive assay procedures on immobilized antibodies A. Variant... 

Plates might be coated at the same time with MAbs of different specificity—individually or in combination with others. The principle of MAbs combination depends on whether there is some preliminary information about their mutual relationship, for example, competitive assay or peptide binding assay. Afterwards, the plates would be sequentially incubated with the same library preparation. 

Immunoassay standard curves. Immunosensors were prepared as described. Sample, standards, and conjugate were added sequentially to the respective cells to start the competitive assay. After a 10 min incubation, the solution was discarded and a proprietary buffer was added to each cell. A sufficient concentration of glucose was then added to each cell to drive the enzyme reaction to maximum velocity. As in the qualification tests, the hydrogen... 

We developed a magnetic beads-based detection system for competitive assay of metabolites from OPs (Figure 3) (4J). This method employed a sequentially injecting washing buffer, a mixture of TCP (chlorpyrifos metabolite) containing sample,... 

New immunoassay concepts were described in which immobilized affinity ligands are used in unique flow-through systems (flow-injection immunoassay, FIIA). These systems are exclusively heterogeneous. Both immobilization of a specific antibody or a hapten on the solid support is possible. In most cases the scheme of the assay used is based on a sequential competitive enzyme immu-noas.say procedure [66], [67],... 

Competitive Immunoassays. In a competitive immunochemical assay, all reactants are mixed together either simultaneously or sequentially. In the simultaneous approach, the labeled antigen (Ag ) and unlabeled antigen (Ag) compete for binding to the antibody. In such a system, the avidity of the antibody for both the labeled and unlabeled antigen must be the same. Under these conditions, the probability of... 

A Zettner, PE Duly. Principles of competitive binding assays (saturation analysis) II. Sequential saturation. Chn Chem 20 5, 1974. 

Immunochemical analysis is a fast developing field with numerous possibilities for further improvement. Much effort is being put into the development of continuous measurements, such as flow-injection immunoanalysis (FI I A) and immunosensors. A quasicontinuous FI IA of pesticides was developed by Kramer and Schmid ) on the basis of a competitive lA. Here, the Abs are immobilized on a membrane. The reaction takes place in the membrane reactor, the central part of the flow injection system. All reagents are sequentially added to the reactor and the product is assayed with the aid of a fiow fiuorimeter. The measuring range of the fiow injection analysis almost equals that of the EIA. Wittmann and Schmid used an Ab column reactor filled with polystyrene or glass beads with the Ab immobilized via the avidin/biotin system. This system showed a stable Ab activity for a minimum of 500... 

---