title: Rapid preparation and quality control method for technetium-99m-2-methoxy isobutyl isonitrile (technetium-99m-sestamibi).
abstract: Technetium-99m-2-methoxy isobutyl isonitrile (99mTc-sestamibi) is a radiopharmaceutical that can be useful in the evaluation of patients with acute myocardial infarction. The current method for preparation requires a lengthy boiling water bath procedure and the recommended quality control procedure is cumbersome and time-consuming. Using a microwave oven, the heating time necessary to provide a labeling efficiency (averaging 97% for sestamibi-labeled with maximum allowable 99mTc activity and volume has been reduced to 10 sec. A new mini-paper chromatography (MPC) system has been developed to analyze the radiochemical purity of 99mTc-sestamibi involving a 1:1 chloroform/tetrahydrofuran developing solvent. The recommended thin-layer chromatography (TLC) system involving the use of an AI2O3-coated plate requires an average time for drying and development of 34.8 +/- 1.6 min (n = 58) to complete, whereas the new MPC system has an average developing time of 2.3 +/- 0.1 min (n = 26). For radiochemical purity values ranging from 71-99% (n = 31), the MPC and TLC methods correlated closely (r = 0.99) with a regression line of MPC% = 1.05 TLC%--5.75. The combined use of the microwave oven heating method and our quick quality control system will facilitate the rapid, emergency use of 99mTc-sestamibi and eliminate the need for advance preparation of multiple kits each day.
authors.affiliation: Department of Radiology, Mayo Clinic, Rochester, MN 55905.
authors.forename: J C
authors.initials: JC
authors.lastname: Hung
authors.forename: M E
authors.initials: ME
authors.lastname: Wilson
authors.forename: M L
authors.initials: ML
authors.lastname: Brown
authors.forename: R J
authors.initials: RJ
authors.lastname: Gibbons
mesh_terms: D002854:Chromatography, Paper / Q000379:methods; D002855:Chromatography, Thin Layer; D006801:Humans; D007553:Isotope Labeling / Q000379:methods*; D008872:Microwaves; D009203:Myocardial Infarction / Q000000981:diagnostic imaging*; D009570:Nitriles; D015609:Organotechnetium Compounds; D011786:Quality Control; D011877:Radionuclide Imaging; D011933:Reagent Kits, Diagnostic; D017256:Technetium Tc 99m Sestamibi; D013997:Time Factors
chemical_list: D009570:Nitriles; D015609:Organotechnetium Compounds; D011933:Reagent Kits, Diagnostic; D017256:Technetium Tc 99m Sestamibi