Initial evaluation of a 99mTc-cyclopentadienyltricarbonyl technetium complex as a potential 5-HT1A receptor imaging agent

•We develop a new 99mTc-labeled for 5-HT1A receptor imaging agent.•A N-phenylferrocenecarboxamide labeled with technetium-99 m (99mTc-2)has been successfully prepared in good yield.•99mTc labeled complex was able to bind specifically to rat hippocampus.•Regional brain distribution study showed a clear correlation between distribution of radioactivity and distribution of 5-HT1A receptors in the brain.•Blocking study confirmed that 99mTc-2 had specific binding to the 5-HT1A receptor.