An experimental study of a technetium-iron complex for scintiscanning.

Abstract A simple technique is described for preparing a technetium iron complex suitable for scanning the brain and kidney. Eluate from the 99Tcm generator added to ferric chloride at pH 1·0 is mixed and deoxygenated by a stream of nitrogen and subsequently raised to pH 7·3 and sterilized. The material has been studied in vitro and in vivo in human subjects by external counting, measurement of activity in serum, urine, stools and saliva as well as by organ scanning, and also by electrophoresis and chromatography of the preparation and of samples of urine and serum. The optimum time for scanning the kidney was three to four hours after giving the dose. Approximately 4 per cent was retained in each kidney in normal subjects up to 30 hours; the mean absorbed dose per 1 mCi administered intravenously in such circumstances was estimated to be 120 mrad to the kidneys and to the whole body 8 mrad.