On-column preparation of 1-aminocyclopentane-1-[11C]carboxylic acid

A new, convenient on-column method using kieselguhr (Extrelut®, Merck) has been developed for the synthesis of 1-aminocyclopentane-1-[11C]carboxylic acid ([11C]ACPC) from [11C]HCN. The whole synthetic procedure, including the trapping and reaction of [11C]HCN as well as the following extraction and acid hydrolysis, was remarkably simplified, and the preparation has been successfully accommodated to routine production of [11C]ACPC. The established method provides radiochemically pure [11C]ACPC in over 60% radiochemical yield within 40 min after the end of bombardment.