Chromatography immunoassay systems

Most immunoassay kits and many commercial immunoassay analyzers are based on heterogenous EIA or FIA. These include an immunoassay system that uses FIA linked to radial partition chromatography of the antibody—antigen complex (39) a system that uses antibody-coated tubes for enzyme immunoassay of a variety of hormones and dmgs (40) and a system that uses either a sandwich or competitive FIA format to measure a variety of analytes (41). 

McConnell RJ, Fitzgerald SP, Lamont JV (1992) Trenbolone and 19-nortestosterone residue analysis by immunoaffinity chromatography and high-performance liquid chromatography and/or an enzyme-linked immunosorbent assay. In Morgan MRA, Smith CJ, Williams PA (eds) Food safety and quality assurance applications of immunoassay systems. Elsevier, Barking, p 245... 

Chemiluminescent immunoassay systems, commercial, 14 151 Chemineer CD6 agitator, 1 739 Chemineer CD6 impeller, 16 673, 701, 703 Chemisorbed water, 23 71 Chemisorption, 1 583-584 for indoor air cleaning, 1 834 parameters of physical adsorption and chemisorption contrasted, l 583t Chemisorption chromatography, 6 405 Chemistry. See also Combinatorial... 

Enzyme immunosensors are used in flow injection systems and Hquid chromatography to provide automated on-line analyses (71—73). These systems are capable of continuously executing the steps involved in the immunoassays, including the binding reactions, washing, and the enzyme reaction, in about 10 minutes. 

General books [213-217], chapters [218], and reviews were published in the 1980s reporting the suitability of CL and BL in chemical analysis [219-222], the specific analytical applications of BL [223], the CL detection systems in the gas phase [224], in chromatography [225, 226], the use of different chemiluminescent tags in immunoassay, and applications in clinical chemistry [227-232] as well as the applications of CL reactions in biomedical analysis [233]. 

Applying different CL systems, continuous-flow CL-based detection of several analytes has been widely applied for determination of several biological compounds and drugs. This technique has already become a highly sensitive method of detection in FIA, in liquid and gas chromatography, and in immunoassays [6-12],... 

Consider one small molecule, phenylalanine. It is an essential amino acid in our diet and is important in protein synthesis (a component of protein), as well as a precursor to tyrosine and neurotransmitters. Phenylalanine is one of several amino acids that are measured in a variety of clinical methods, which include immunoassay, fluorometry, high performance liquid chromatography (HPLC see Section 4.1.2) and most recently MS/MS (see Chapter 3). Historically, screening labs utilized immunoassays or fluorimetric analysis. Diagnostic metabolic labs used the amino acid analyzer, which was a form of HPLC. Most recently, the tandem mass spectrometer has been used extensively in screening labs to analyze amino acids or in diagnostic labs as a universal detector for GC and LC techniques. Why did MS/MS replace older technological systems The answer to this question lies in the power of mass spectrometer. 

Protein pharmaceuticals are so complex that multiple methods are required to gain a complete picture of the sample. Methods are often used in combination. For example, a chromatography system may be used to analyze fluorescent reactants from an immunoassay-based method. 

Examples exist of different types of immunobased technology being interfaced to produce an effective analytical system. In a variety of recent methods, immunoaffinity chromatography has been employed for purification, chemiluminescence enzyme immunoassay has been used for quantification of salbutamol and clenbuterol in tissue and plasma from calves and pigs (122), clenbuterol in cattle hair (123), and monensin in chicken tissues (124). In these methods, quantification at sub-ppb levels has been demonstrated. 

Monitoring a liquid chromatographic effluent by means of an immunoassay provides sensitive and se-leetive deteetion in combination with the separation of eross-reaetive compounds [1,2]. When implementing the immunoassay as a postcolumn reaction detection system after liquid chromatography, it is frequently referred to as immunodetection [3,4]. Automation and assay speed are the main advantages of immunodetection over off-line eoupling of immunoassays to liquid ehromatography by means of fraction collection [5,6]. 

The approach of implementing a biological assay as a postcolumn reaction detection system after liquid chromatography can not only be applied to antibody-based assays (immunoassays) but also to assays employing other affinity interactions with high association and low dissociation rate constants, such as receptors. Information obtained from such a detection system not only provides quantitative results but also indicates the biological activity of the detected compound. 

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