Biological reduction and intracellular trapping differences of 188Re(VII) and 99Tcm(VII) in Escherichia coli

99Tcm is the most commonly used diagnostic radioisotope.And 188Re is an excellent therapeutic radioisotope with a gamma photon for imaging.Both locate in the same group and have very similar properties. 99Tcm(VII)can be partially reduced to a black insoluble precipitate by aerobic cultures of Escherichia coli,and trapped intracellularly.However,188Re(VII)cannot be reduced and trapped,because of its lower oxidizing power of perrhenate as compared with pertechnetate or other reasons.