Immunoassay drug analysis

Today such analyzers are discrete analyzers operating at high throughput on a wider menu of tests than their large cousins. They are usually suited to more sophisticated chemistries, such as those used in specific protein analysis or enzyme-mediated immunoassays for drug analysis. 

Immunoassay analysis of the extracts was performed using Syva assay kits and an AutoLab system. The extract (50 /jL) and assay buffer (250 /jL) were delivered into a reaction cup, followed by 50 jiL reagent A (antibody and substrate) plus another 250 /uL assay buffer, incubated for 50 sec, and mixed with 50 /./I. reagent B (drug-labeled enzyme) plus 250 /uL assay buffer. The change in absorbance of this final mixture was monitored at a wavelength of 340 nm by a spectrophotometer. 

The standard urine immunoassay for detection of cocaine (23a) abuse during the gestation period of newborn babies was frequently found to yield negative results in cases where positive results were shown by extraction of meconium with a solvent, followed by HPLC. The drug and metabolites such as norcocaine (23b) and cocaethyline (23c) were detected140. See Section IV.C for an alternative analysis of cocaine. 

J Caslavska, D Allemann, W Thormann. Analysis of urinary drugs of abuse by a multianalyte capillary electrophoretic immunoassay. J Chromatogr A 838 197-211, 1999. 

Applications. Immunoassays are used in many different disciplines, having clinical, industrial, agricultural, and environmental applications. This technique has made possible rapid analysis of such varied analytes as viruses, toxins, hormones, foreign proteins, drugs, and insecticides. 

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