Projects

125I-labeled peptides

For the receptor studies with biologically active peptides very high specific activities are needed. As amino acid tyrosine is very often present in the peptide chain, the introduction of carrier free radioactive iodine by electrophilic aromatic substitution on activated tyrosin benzene ring is very convenient way to achieve specific activities over 1 000 Ci/mmol of peptide. The resulting mixture of the starting peptide and its monoiodinated and diiodinated derivatives is separated using radio-HPLC. Recently we prepared the following labeled peptides: Trp-Lys-[125I]Tyr-Met-Val-Met-NH2, [125I]CART(61-102), [125I][d(CH2)51, Tyr(Me)2, Thr4, Orn8, Tyr-NH29]vasotocin.

 

3H-labeled steroids

[3H]Pregnenolone-3-O-sulfate ammonium salt and 3α-hydroxy-[3H]pregnanolone 3-O-sulfate ammonium salt were prepared with specific activities 47.5 Ci/mmol and 40 Ci/mmol, respectively. The receptor binding experiments with these labeled steroids gave unexpected results. The project aiming the preparation of 3H labeled brassinosteroids with specific activity higher than 60 Ci/mmol is under way.

 


14C-labeled compounds

At the present time our laboratory facilties are undergoing renovation. We hope to have the capacity to synthetize 14C-labeled compounds by the end of 2008.