Uptake kinetics and biodistribution of 14C- d-luciferin—a radiolabeled substrate for the firefly luciferase catalyzed bioluminescence reaction: impact on bioluminescence based reporter gene imaging. - Berger, Frank; Paulmurugan, Ramasamy; Bhaumik, Srabani; Gambhir, Sanjiv Sam (European Journal of Nuclear Medicine & Molecular Imaging, 2008)