The first enzymatic method for C–18F bond formation: the synthesis of 5′-[18F]-fluoro-5′-deoxyadenosine for imaging with PET

The use of the key enzyme involved in carbon–fluorine bond formation in Streptomyces cattleya catalysing the formation of 5′-fluoro-5′-deoxyadenosine (5′-FDA) from fluoride ion and S-adenosyl-l-methionine (SAM) was explored for its potential application in fluorine-18 labelling of the adenosine derivative. Enzymatic radiolabelling of [18F]-5′-FDA was successfully carried out starting from SAM and [18F]HF when the concentration of the enzyme preparation was increased from sub-mg/ml values to mg/ml values. The purity of the enzyme had no measurable effect on the radiochemical yield of the reaction and the radiochemical purity of [18F]-5′-FDA. Copyright © 2003 John Wiley & Sons, Ltd.