On the preparation of freeze dried calcium phytate kit for Tc-99m labelling

99mTc-phytate is used as an intravenous injection for scintigraphy of the reiculoendothelial system. This complex was first prepared by simply adding 99mTc-pertechnetate to the Sn(II)-phytate then injected intravenously to form in vivo radioactive colloid with the Ca+2 present in the blood. The main target organ for this preparation is the liver. This preparation was modified by adding Ca+2 to the 99mTc phytate solution before injection, the colloid was stabilized by adding gelatin or human serum albumin to the preparation just before or after Ca+2 addition. This colloidal preparation is further modified in the phytate amount and simplified by freeze drying the Sn-phytate complex and polyvinylpyrrolidone (PVP) as stabilizer in one vial. To prepare 99mTmc-colloid, 99mTc-pertechnetate is added, followed by Ca+2 addition. This preparation is used for liver and spleen scanning, work on labelling a preformed Sn-phytate colloid with 99mTc is being carried out. The quality of the labelled product is studied by radiochemical analysis and biological distribution