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PubMed · 15264884

Labeling of steroids on solid phase.

Jari Peuralahti·Katriina Suonpää·Kaj Blomberg·Veli-Matti Mukkala·Jari Hovinen
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Abstract

Up to four tetra-tert-butyl-1-[4-aminoacetamido)benzyl]diethylenetriaminetetrakis(acetato) derivatives of Fmoc glutamic acid (1) were attached to two steroids (17alpha-hydroxyprogesterone-3-O-carboxymethyloxime 2 and 1,3,5(10)-estratriene-3,16alpha,17beta-triol-6-one-6-O-carboxymethyloxime, 3)) on solid phase using an oligopeptide synthesizer. Upon deprotection and conversion to the corresponding europium(III) chelates, these steroid conjugates were used in DELFIA-based competitive fluoroimmunoassays. The more chelates conjugated to 17-alpha-hydroxyprogesterone, the more diluted antiserum could be used in an immunoassay for 17-alpha-hydroxyprogesterone, without any alteration of the measurement range. Hence, 17-alpha-hydroxyprogesterone tracers with several chelates are useful when a high serum dilution factor is desired i.e., when only a limited quantity of antiserum is available. The result demonstrates the suitability and usefulness of lanthanide(III) chelates as multilabels in bioaffinity assays.

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Chromatography, High Pressure LiquidImmunoassayMolecular StructureStaining and LabelingSteroidsJournal Article

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Jari Peuralahti, Katriina Suonpää, Kaj Blomberg, Veli-Matti Mukkala, Jari Hovinen. Labeling of steroids on solid phase.. https://doi.org/10.1021/bc049929p

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