The present disclosure relates to a compound comprising at least one of a carbon or an oxygen isotope and a process for preparing the compound. The process comprises irradiating a compound comprising at least one of a carbon or an oxygen atom using photons or particles having an energy in the range of 20 MeV-430 MeV. The carbon and/or the oxygen atom is then allowed to be converted into a carbon and/or an oxygen positron nuclide through a photonuclear reaction. Provided that the molecular structure of the compound is not disrupted, the compound comprising the carbon and/or the oxygen isotope is prepared. The compound may be used in positron and/or other nuclide imaging to obtain a distribution and/or metabolic image of the compound in a human and/or animal body.
