A rapid and economical method of preparing radioiodinated cyclic nucleotide derivatives for use in radioimmunoassays.
2'-O-succinyladenosine 3':5'-cyclic monophosphate tyrosyl methyl ester (ScAMP-TME) and 2'-O-succinylguanosine 3':5'-cyclic monophosphate tyrosyl methyl ester (ScGMP-TME) were radioiodinated using chloramine T and Na125I. The resulting radiolabeled cyclic nucleotide derivatives, ScAMP-125I-TME and ScGMP-125I-TME, were subsequently purified by reverse-phase chromatography on Sep-Pak C18 cartridges (Waters Associates, Milford, MA) and tested as tracers in sensitive radioimmunoassays for cAMP and cGMP, respectively. Purified ScAMP-125I-TME and ScGMP-125I-TME functioned in the respective radioimmunoassays for up to 12 weeks when suspended in a 1:1 (v:v) mixture of n-propanol and 20 mM sodium acetate, pH 6.0. Thus, this purification method enables rapid and economical preparation of tracers for cyclic nucleotide radioimmunoassays. Furthermore, our findings suggest that reverse-phase chromatography may be applicable to the purification of other small polar molecules to which tyrosyl groups have been added for the purpose of radioiodination.
Oehlenschlager
W F
WF
Medical University of South Carolina, Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Charleston 29425.
Kubalak
S W
SW
Currie
M G
MG
D000242:Cyclic AMP / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000302:isolation & purification; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000302:isolation & purification; D007457:Iodine Radioisotopes; D007553:Isotope Labeling; D011863:Radioimmunoassay; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000302:isolation & purification
D007457:Iodine Radioisotopes; D014443:Tyrosine; C043118:succinyl cyclic AMP-tyrosine methyl ester; C014832:succinyl cyclic GMP-tyrosine methyl ester; D000242:Cyclic AMP; D006152:Cyclic GMP