Kit (nonradioactive precursor) for the preparation of an enantiomeric form of the renal function diagnostic technetium-99m-mercaptoacetyltriglycine (99m-Tc-MAG-3) and method of making the kit

摘要

The invention relates to an inactive composition (kit) for preparing a stable enantiomeric form of technetium-99m mercaptoacetyltriglycine (99mTc-MAG-3) for nuclear medical examinations of kidney function, and to a process for producing this kit. The kit according to the invention consists of two components which are packed separately and the first of which consists of a lyophilised mixture of mercaptoacetyltriglycine, of a coligand stabilising oxidation state +5 of Tc, of a reducing agent and alkali metal or alkaline earth metal hydroxide in the molar ratio 1 : (50 - 150) : (0.1 - 0.5) : (30 - 80 MAG-3 : coligand : reducing agent : hydroxide and whose second component contains a sterile phosphate buffer solution with an amount of acid corresponding to the molar ratio MAG-3 : hydroxide. Used for this purpose in a preferred embodiment is a salt of tartaric acid or gluconic acid, in particular Na2 tartrate, as coligand, SnCl2 as reducing agent, and NaOH as hydroxide. Concerning the process, the invention comprises, for the preparation of component 1 of the kit, hydrolysing benzoyl-MAG-3 with alcoholate in alcoholic solution and mixing the mercaptoacetyltriglycine ligand obtained in this way with the mercapto group in unprotected form with the reducing agent and with the coligand which stabilises oxidation state +5 of Tc at pH 11 in the ratio indicated above, lyophilising and packing in portions.