Enzyme EMIT

A basic mechanism that is believed to be responsible for this difference in activity involves release of the organotin. In cases where the comonomer is biologically active, release of the comonomer drug occurred through either simple physical hydrolysis or through hydrolysis initiated or is assisted by hydrolyzing enzymes emitted by the particular microorganism. It is uncertain if the polymer, some... 

The preparations of luciferin (Ln, an electron acceptor) and soluble enzyme used were crude or only partially purified. The luciferase was an insoluble particulate material, possibly composed of many substances having various functions. Moreover, the luciferin-luciferase reaction was negative when both luciferin and luciferase were prepared from certain species of luminous fungus. It appears that the light production reported was the result of a complex mechanism involving unknown substances in the test mixture, and probably the crucial step of the light-emitting reaction is not represented by the above schemes. 

The use of the fire fly light-emitting system. Light generation depends on the oxidation of a substance known as luciferin. This is a fatty aldehyde such as dodecanal. An enzyme called luciferase, extracted from fire flies, catalyses the oxidation. The reaction also requires ATP. Thus, light emission measures ATP. 

All specimens were analyzed by EMIT (Enzyme Immunoassay Technique), an enzyme method based upon the competitive bonding of an enzyme and an antibody. This method yields a positive result with concentrations of 75 ng of PCP/ml or greater (Rubenstein et al. 

Five anticonvulsants including valproic acid were determined by the Abbott TD x fluorescence polarization immunoassay automatic analyzer. Recoveries were 94.8-106% and the coefficients of variations were 1.0-9.7% [23], Fluorescence polarization immunoassay and enzyme immunoassay were compared for the determination of free valproic acid in serum [24], Good correlation (R = 0.9992) was obtained between the two assays. Higgins [25] reported on the determination of valproic acid in serum by enzyme immunoassay with use of EMIT reagents and the Abbot ABA-200 analyzer. Responses were rectilinear up to 150 mg/L. 

Bioluminescence and chemiluminescence are very powerful analytical tools, since in addition to the direct measurement of ATP, NAD(P)H or hydrogen peroxide, any compound or enzyme involved in a reaction that generates or consumes these metabolites can be theoretically assayed by one of the appropriate light-emitting reactions. Some of these possibilities have been exploited for the development of optical fibre sensors, mainly with bacterial bioluminescence and with luminol chemiluminescence. 

Pankey et al.21 described a rapid, reliable, and specific enzyme multiplied immunoassay technique (EMIT ) for amitriptyline, nortriptyline, imipramine, and desipramine in sera. To overcome crossreactivity, solid phase extraction was included in sample pretreatment. Disposable 1 mL columns packed with covalently labeled silica gel were conditioned with HPLC-grade methanol (1 mL) and then with de-ionized or distilled water (1 mL). Serum (calibrator, control, or patient sample, 500 L) was applied onto the column, eluted to waste, washed with 900 /uL of wash solution containing acetonitrile (236.1 g/L) and ion-pairing reagent in acetate buffer, pH 4.2, washed with 500 fiL of mobile phase solution containing acetonitrile (393.5 g/L) in methanolic phosphate buffer, pH 7.0,... 

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