Antibody-immobilization

The amount of antibody immobilized on the sensor chip decreased with increasing concentration of methyl viologen. To enlarge the difference in the sig-... 

A novel fiber optic sensor concept using antibody-antigen reactions at a glass-liquid interface was reported by Daehne146. The reaction of antibodies immobilized onto the surface of fused silica fiber optic or planar waveguides with antigens in solution was detected by interaction with the evanescent wave. By detecting in-line fluorescence, the measurement of human IgG is described. 

Narang U., Anderson G.P., King K.D., Liss H.S., Ligler F.S., Enhanced biosensor performance using an avidin-biotin bridge for antibody immobilization, Proc. SPIE. 2980 187-194,1997. 

Peluso P., Wilson D.S., Do D., Tran H., Venkatasubbaiah M., Quincy D., Heidecker B., Poindexter K., Tolani N., Phelan M., Witte K., Jung L.S., Wagner P., Nock S., Optimizing antibody immobilization strategies for the construction of protein microarrays, Anal Biochem. 2003 312 113-124. 

Brillhart, K.L., and Ngo, T.T. (1991) Use of microwell plates carrying hydrazide groups to enhance antibody immobilization in enzyme immunoassays./. Immunol. Meth. 144, 19-25. 

Antibody immobilization Antigen immobilization Ag-hapten immobilization... 

They found that the hydrolysis products of 4-AP and 1-naphthol produced well-defined anodic responses at low potentials at a bare SPCE. However, the presence of antibody immobilized on the electrode surface slowed the diffusion of 4-AP towards the electrode surface. In addition, 4-AP may interact with polyphenols on the electrode surface, thus reducing the electroactive working area of the electrode by fouling. In contrast, diffusion of 1-naphthol to the electrode surface was not hindered by immobilized antibody. This feature, along with its low cost, ease of availability, and high solubility, resulted in 1-NP being the preferred AP substrate in their work. 

O. Ouerghi, A. Touhami, N. Jaffrezic-Renault, C. Martelet, H. Ben Ouada, and S. Cosnier, Impedimetric immunosensor using avidin-biotin for antibody immobilization. Bioelectrochemistry 56, 131—133... 

Conductometric transducers, as the oldest electrochemical devices, seem not to enjoy wide applications due to their poor selectivity. For example, Yagiuda et al. proposed a conductometric immunosensor for the determination of methamphetamine (MA) in urine [89], The decrease in the conductivity between a pair of platinum electrodes might result from the direct attachment of MA onto the anti-MA antibodies immobilized on the electrode surface. The system was claimed to be a useful detection technique of MA in comparison with a gas chromatography-mass spectrometry method. 

Z.Y. Wu, Y.H. Yan, G.L. Shen, and R.Q. Yu, A novel approach of antibody immobilization based on n-butyl amine plasma-polymerized films for immunosensors. Anal. Chim. Acta 412, 29-35 (2000). 

A continuous semiautomated FIIA system has been reported [208,235]. In this device the analyte-containing medium is allowed to flow through a column containing the antibodies immobilized on a support. First, the antibodies are saturated with a fluorescent dye-labeled analog of the analyte. As the analyte passes through the immunosorbent, some dye-labeled antigen is displaced and is then detected in a fluorometer located downstream from the column. The LOD achieved for the developed system is 1 pg L 1. 

Antigen-Antibody Immobilization of Glucose Oxidase. Kinetic Analysis... 

The general method utilized to prepare E5-Ab solutions obviates the need for stocking large numbers of reagents which would be necessary if different activation methods were used for each antibody. A number of specific antibodies immobilized by this process have shown response similar to that of the same antibodies when adsorbed as immune complexes in the Stratus system. In addition, the dendrimer-coupled antibodies have shown dramatic improvements in sensitivity, flexibility and precision for the enzyme immunoassay system. Feasibility demonstration of an assay for DNA probes is a prelude to what can possibly be achieved with these dendrimer-based reagents. 

The devices usually contain antibody immobilized on a membrane surface above a filter and absorbent pad (Figure 7.16). The sample is placed in the device and passes through the membrane into the absorbent pad. Where analyte is present in the sample it is sequestered by the antibody on the membrane and is then visualized by addition of a labelled second antibody. Labelled second antibody not bound to analyte also passes into the absorbent pad, sometimes with the aid of a wash solution. The labelled molecule may be an enzyme, which would then require addition of a suitable substrate, or a label such as colloidal gold, which has the virtue of being visible without the aid of a second reagent. 

The surface activation time of the polymer required for maximum site activity for binding antibodies was determined by evaluating the fluorescence intensity of a series of probes incubated in inorganic acids at different times. Knowledge of the surface activation time is necessary to obtain maximum activation, thus allowing maximum antibody immobilization on the probe. Consequently, lower detection limits may be achieved. 

In order to determine the minimum incubation time required for maximum antibody immobilization on the probe s reaction phase, the activated probes were... 

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