ABSTRACT
An immunoassay method based on the labelling of an antigen with a transition-metal carbonyl organometallic marker and detection of the label by Fourier transform infrared (FT-IR) spectroscopy is described. The viability of this novel non-isotopic approach, termed infrared immunoassay (IRIA), has been evaluated in the quantitative determination of the tricyclic antidepressant nortriptyline.
Subject(s)
Spectrophotometry, Infrared , Animals , Antibodies/analysis , Fourier Analysis , Immunoassay/methods , Nortriptyline/analysis , Organometallic Compounds/metabolism , RabbitsABSTRACT
Metalloimmunoassay is a new immunoassay using an organometallic complex as the label. For the development of this assay, antibodies were produced in rabbits immunized with N-succinyldesipramine-bovine serum albumin conjugate. Antisera thus obtained were shown to be specific for the tricyclic antidepressant group of drugs and are tested as regard as desipramine or nortriptyline labelled by an organometallic moiety (designated metallohaptens). The evaluation of the affinity constants shows that antisera cross-react almost equally well with both imipramine labelled with tritium (radiotracer) and metallohaptens using either ferrocene or cymantrene as labels (metallotracers). Detection of metallohaptens is performed by a ZEEMAN atomic absorption spectrophotometer (ZAAS).