The invention is directed to radiolabelled MMP selective compounds, a processes for the preparation thereof, and uses thereof. The derivatives of the invention have formula (I) wherein Y represents O, CH2, (CH2)2, S, NH, or C(═O)NH; X represents 1-5 substituents, wherein said substituents can be the same or different and wherein at least one of said substituents comprises a radioisotope suitable for PET and/or SPECT and/or a β-emitter; Z is S; Q is chosen from the group consisting of 3-pyridyl and carboxyl; and R is chosen from the group consisting of C(═O)—NH—OH, (II), (III, (IV). The MMP selective compounds of the invention are selective for MMPs and can be used for the identification and treatment of unstable atherosclerotic plaques.