Barbiturates radioimmunoassay

Part—VI has been solely devoted to Miscellaneous Assay Methods wherein radioimmunoassay (RIA) (Chapter 32) has been discussed extensively. Various arms of theoretical aspects viz., hapten determinants and purity importance of antigenic determinants and analysis of competitive antibody binding of isotopically labeled compounds. The applications of RIA in pharmaceutical analysis, such as morphine, hydromorphone and hydrocordone in human plasma clonazepam, flurazepam in human plasma chlordiazepoxide in plasma barbiturates, flunisolide in human plasma have been described elaborately. Lastly, the novel applications of RIA-techniques, combined RIA-technique-isotope dilution and stereospecificity have also been included to highlight the importance of RIA in the analytical armamentarium. 

Relatively new but quickly adopted and developed analytical methods for barbiturates are the enzyme and radioimmunoassay techniques.497 The principles and procedures have been reviewed498-502 and comparisons between these and other analytical methods are available.233,503-512... 

SJ Mule, E Whitlock, D Jukofsky. Radioimmunoassay of drugs subject to abuse Critical evaluation of urinary morphine-barbiturate morphine, barbiturate and amphetamine assays. Clin Chem 21 81, 1975. 

EJ Flynn, S Spector. Determination of barbiturate derivatives by radioimmunoassay. J Pharmacol Exp Ther 181 547, 1972. 

Fl)mn and Spector [55] developed a radioimmunoassay for a number of barbiturates, including thiopental. The sensitivity for the latter was 100 ng, a figure tenfold higher than for its oxo-analogue, pentobarbital. This indicated that the urea portion of the ring was critical in determining antibody qsecificity [55]. 

Seto A, Tricomi S, Goodwin D, Kolodney R, Sullivan TJ (1978) Biochemical correlates of ethanol induced flushing in Orientals. J Stud Alcohol 39 1-11 Spector S, Parker CW (1970) Morphine radioimmunoassay. Science 168 1347-1348 Spector S, Berkowitz B, Flynn EJ, Peskar B (1973) Antibodies to morphine, barbiturates, and serotonin. Pharmacol Rev 25 281-291... 

Mass Screening and Confirmation of Barbiturates in Urine by RIA [Radioimmunoassay]/Gas Chromatography... 

Mueller, M. A., and Wang, R. I. H. Comparison of Radioimmunoassay with Thin-Layer and Gas-Liquid Chromatographic Methods of Barbiturate Detection in Human Urine Clin. Chem. (Winston-Salem, N. C.) 21(6) 672-675 (1975) CA 83 ... 

Antibodies have been raised against barbiturates enabling them to be assayed by radioimmunoassay or enzyme-immunoassay. 

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