FOLH1 and neoplasm: Compared to the neutral and positively charged tricarbonyl core-bearing radioligands published by Banerjee et al. the in vivo performance of the anionic 99mTc-tricarbonyl complex 99mTc-TMCE is characterized by a relatively long blood circulation and fast washout from the tumor (blood: 11.4 ± 2.3, 3.2 ± 0.5, 0.6 ± 0.6 ± 0.1 % IA/g and LNCaT-tumor: 4.0 ± 1.2, 12.8 ± 2.2 and 5.0 ± 2.7 % IA/g at 5, 30 and 120 min p.i. respectively) The outcome of the study demonstrated the effect of affinity, hydrophilicity, and electric charge in the pharmacokinetics of PSMA imaging probes.