3-([3-125I]Iodo-4-hydroxyphenyl)propionyl Carbohydrazide, a new radioiodination reagent for ultrasensitive detection and determination of periodate-oxidized nucleoside derivatives

A new radioiodination reagent for the identification and quantitation of periodate-oxidized ribonucleosides was developed. The reagent, 3-([3-125I]iodo-4-hydroxyphenyl)propionyl carbohydrazide, was prepared by radioiodination of 3-(4-hydroxyphenyl)propionic acid N-hydroxysuccinimide ester in the presence of chloramine T, followed by reduction of the latter with sodium arsenite and treatment of the radioiodinated ester with an excess of carbohydrazide. The reagent reacted quantitatively with periodate-oxidized nucleosides to form 125I-labeled morpholine derivatives which were separated by thin-layer chromatography and quantitated by liquid scintillation counting. The reagent was found to react also with other carbonyl compounds and thus may find more general application in the qualitative and quantitative ultramicroanalysis of aldehydes and ketones