Immunoassay applicability

The development of sensitive and inexpensive immunoassays for low molecular weight pesticides has been an important trend in environmental and analytical sciences during the past two decades. 0.27-29 jq design an immunoassay for a pesticide, one can rely on the immunoassay literature for agrochemicals, " but many of the innovations in clinical immunoanalysis are also directly applicable to environmental analysis. - Conversely, the exquisite sensitivity required and difficult matrices present for many environmental immunoassay applications have forced the development of technologies that are also useful in clinical immunoassay applications. In the following discussion we will describe widely accepted procedures for the development of pesticide immunoassays. 

The aim of this chapter is to discuss fluorescence concepts that are used in selected immunoassay applications. The primary focus is on fluorescence topics of recent interest that provide insight into the characteristic properties of antibodies and antigens in immunoassays, or that describe enhancements in immunoassay technologies. The basic reagents and instrumentation required for immunoassay purposes are discussed first, followed by a brief description of immunoassay formats. The principles that are utilized in various fluorescence immunoassay technologies are outlined with specific examples and their significance. Since it is beyond the scope of this chapter to review all of the applications of fluorescence immunoassays, apologies are extended to authors that this chapter fails to cite. A number of comprehensive treatments of fluorescence immunoassay (FIA) applications and related topics are available. 18 ... 

Massayeff, R. and Maillini, R. (1975) A sandwich method of enzyme immunoassay. Application to rat and human a-fetoprotein. J. Immunol. Methods 8,223-234. 

FIGURE 5.18 Illustration of the flow confinement concept. In microchannels, a sample flow is joined with a confinement flow (e.g., water or sample medium) in a perpendicular orientation. Under laminar flow conditions, no mixing occurs. The sample flow is confined into a thin layer of higher velocity. For immunoassay application, rabbit IgG is immobilized on a planar waveguide and Cy5-labeled anti-rabbit IgG is introduced as analyte in the sample flow [694]. Reprinted with permission from the American Chemical Society. 

Lee, H.A. and Morgan, M.R.A. 1993. Food immunoassay Applications of polyclonal, monoclonal and recombinant antibodies. Trends Food Sci Technol 4 129-132. 

Yang, W., Trau, D., Renneberg, R., Yu, N. T., and Caruso, F. (2001). Layer-by-Layer construction of novel biofunctional fluorescent microparticles for immunoassay applications. J. Colloid Interface Sci. 234 356-362. 

Immunoassays, along with all other methods based on biorecognition, are a great achievement for the field of analjdical chemistry. The first area to benefit from the advantages of this technique is probably chnical analysis, where selective and sensitive determination of macromolecules is often necessary, as it is very difficult, or sometimes impossible to identify and quantify macromolecules by any alternative method. Recently, the immunoassay application field was extended, more or less successfiilly, to the determination of small molecules (below 1000 Da) as well. The acceptance of immunoassays is, however, relatively hmited in some fields, probably due to the differences between the classical analytical methods and immunoassays, the latter requiring special conditions of operation, characterization and data interpretation, due to the extraordinary nature of the antibody-antigen interaction, as well as that of many possible interfering reactions. 

Borg, A., Lennerstrand, J., Stenmark-Askmalm, M., Femo, M., Brisfors, A., Ohrvik, A., Stal, O., Killander, D., Lane, D., and Brundell, J. (1995) Prognostic significance of p53 overexpression in primary breast cancer a novel luminometric immunoassay applicable on steroid receptor cytosols. Br. J. Cancer 71,1013-1017. 

The uses to which microreactors have been applied are diverse and cover many fields. Examples cited here include organic synthesis, combustion, reforming, and immunoassay applications. These are only a small sample of the applications to which microreactors have been applied and without doubt an even smaller sample of the future applications of these unique reaction systems. 

For the intended immunoassay application, a semiquantitative format is used. Sample response in the cartridge is compared to the responses from two standards to determine whether the sample is above (positive) or below (negative) a user-selected level. The total time for the atrazine assay was optimized at 15 min a 10 min incubation and a 5 min response time. Recent results have demonstrated the efficacy of this format in discriminating positives and negatives around the decision point of 3 ppb atrazine [39]. 

A. Dankwardt,S. Pullen, B. Hock, Immunoassays. Applications for the Aquatic Environment , in Microscale Aquatic Toxicology - Advances, Techniques and Practice, eds. P.G. Weils, K. Lee, C. Blaise, CRC Lewis Publishers, Florida, 13-29,1998. 

C3. CatteraU, J. B., and Cawston, T. E., Assays of matrix metaUoproteinases (MMPs) and MMP inhibitors Bioassays and immunoassays applicable to cell culture medium, serum, and synovial fluid. Methods Mol. Biol. 225, 353-364 (2003). 

See also Blood and Plasma. Hormones Steroids. Immunoassays, Applications Clinical. Quality Assurance Reference Materials. 

See also-. Clinical Analysis Overview. Electrophoresis Clinical Applications. Immunoassays, Applications ... 

See also Amino Acids. Electrophoresis Proteins. Food and Nutritional Analysis Overview Antioxidants and Presen/atives. Immunoassays, Applications Food. Immunoassays, Techniques Luminescence Immunoassays. Kinetic Methods Principles and Instrumentation. Liquid Chromatography Food Applications. Proteins Foods. Vitamins Overview. 

Immunoassays, Applications Food. Liquid Chromatography Food Applications. Nitrosamines. Polychlorinated Biphenyls. Quality Assurance Reference Materials Production of Reference Materials. Sampling Theory. Sensors Overview. Surfactants and Detergents. 

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