Preparation, radiochemical purity control and stability of 99mTc-mertiatide (Mag-3).
BACKGROUND
Scintigraphic image analysis of 99mTc-mertiatide (Mag-3, mercaptoacetyltriglycine) clearance provides the determination of the blood flow, the tubular transit time and the excretion as well from both kidneys. Radiopharmaceutical routine recommends a radiochemical purity control before administration of the product to a patient. The main objective of this study is to develop a Mag-3 labeling procedure that fits better than the previous one in our daily routine production of radiopharmaceuticals.


METHODS
Increasing proportions of 99mTc-Mag-3 were measured during the heating and cooling steps of the Mag-3 labeling procedure. HPLC analysis was used to confirm the results of a rapid radiochemical quality control assay on standard ITLC-SG paper.


RESULTS
The reconstitution time takes 20-25 minutes from the harvest of pertechnetate to a ready-for-use calibrated patient syringe. The HPLC profile of 99mTc-Mag-3 including its minor impurities remains unchanged for 24-48 hours after reconstitution.


CONCLUSIONS
The application of a programmable Peltier-directed device for heating/cooling provides a better control of the temperature course. The procedure proposed fully meets the labeling criteria recommended by the supplier and can be performed with a minimum of attention within a time-span that we formerly needed for solely the radiochemical purity control assay. Moreover, 99mTc-Mag-3 prepared in this way seems to be considerably more stable than mentioned in the manufacturer's instructions.
van Hemert
Formijn J
FJ
Department of Nuclear Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands. f.j.vanhemert@amc.uva.nl
van Lenthe
Henk
H
Schimmel
Kirsten J M
KJ
van Eck-Smit
Berthe L F
BL
D002845:Chromatography / Q000379:methods; D007553:Isotope Labeling / Q000379:methods; D019275:Radiopharmaceuticals / Q000032:analysis / Q000138:chemical synthesis; D017263:Technetium Tc 99m Mertiatide / Q000032:analysis* / Q000737:chemistry*
D019275:Radiopharmaceuticals; D017263:Technetium Tc 99m Mertiatide