Spectrophotometric determination of Sn(II) using palladium chloride in kits for 99mTc radiopharmaceuticals

A method of quantitating Sn(II) suitable for the analysis of kits for 99mTc radiopharmaceuticals, based on a spectrophotometric determination using the Pd(II)-Sn(II) complex (yellow species) is described. The absorbance of the complex is measured at 410 nm and Beer's law is obeyed up to 250 micrograms Sn(II) in the aqueous phase. Several radiopharmaceutical kits were analyzed for their Sn(II) content. The investigation indicates that the procedure is simple, rapid and accurate for quantitative estimation of Sn(II) in various 99mTc-labelling kits during development, manufacture and storage.