Radiokémiai Fejlesztő Munkacsoport Kutatócsoport

The workgroup was established to support the activity of the Biological Research Group to supply it with new radiolabelled compounds. With this object we have synthesized some well known radiotracers, such as 1-[18F]Fluoro-3-(2-nitroimidazol-1-yl)-propan-2-ol (18F-MISO), 9-[(4-[18F]Fluoro-3-hydroxymethybutyl)]guanine (18F-FHBG), O-(2-[18F]Fluoroethyl)-L-tyrosine (18F-FET), 3-(2-[18F]Fluoro)flumazenil. We participated in the radiolabelling of some biologically active macromolecules, such as oligonucleotides, serum albumins, Rhodamin B. We are especially interested in chemoselective radiolabelling of some, receptor specific peptide sequences, and we have fluorinated analogues for LH-RH-, somatostatin- and gastrin releasing peptide receptors starting the procedure from 18F-4-Fluorobenzaldehyde. This kind of ligation yields neutral peptide derivatives. If the radiolabelling is performed with radiometals, we get a positively charged peptide and this property will affect the biodistribution and clearance of the ligand. Therefore this approach can be interesting. With this object we are going to label receptor selective peptides with 68Ga. We are also working on introduction of new, promising radiofluorination methods into our in-house practice. We have performed a couple of syntheses on 18F-Fluoroethyl tosylate using recently published reaction media, such as ionic liquids, bulky protic solvents. The goal of these experiments is to work out effective methods for aliphatic nucleophilic substitution.