The influence of generator eluate on the radiochemical purity of 99Tcm-sestamibi prepared using fractionated Cardiolite kits.
The reconstitution of fractionated Cardiolite kits with sodium 99Tcm-pertechnetate eluted from a wet-column 99Mo/99Tcm generator results in a preparation that contains elevated amounts of a polar radiochemical impurity, which is normally present in only trace amounts when such kits are reconstituted with eluate from a dry-column generator. A consequence of this impurity, which appears to be an organotechnetium compound, is that it causes a positive bias in several quality control methods for 99Tcm-sestamibi, including that recommended by the manufacturer. This impurity was isolated, and its biodistribution determined in Wistar rats. Two alternative methods for the preparation of 99Tcm-sestamibi from fractionated Cardiolite kits using eluate from a wet-column generator were investigated. A rapid procedure, based on a C18 solid phase extraction (SPE) cartridge, for measuring the radiochemical purity of 99Tcm-sestamibi samples, which had been prepared using fractionated Cardiolite kits, was developed and compared with two other methods including high-performance liquid chromatography (HPLC). Over a radiochemical purity range of 49-98%, the values obtained using our quality control method deviated from those obtained using HPLC by 1.1 +/- 1.3% (n = 26). In contrast to some of the rapid quality control methods assessed in our investigation, the SPE technique was not biased by the presence of the organotechnetium impurity.
Varelis
P
P
Department of Nuclear Medicine, St George Hospital, Kogarah, NSW, Australia.
Parkes
S L
SL
Poot
M T
MT
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D002854:Chromatography, Paper; D002855:Chromatography, Thin Layer; D019275:Radiopharmaceuticals / Q000737:chemistry* / Q000302:isolation & purification / Q000493:pharmacokinetics; D051381:Rats; D011933:Reagent Kits, Diagnostic; D017256:Technetium Tc 99m Sestamibi / Q000737:chemistry* / Q000302:isolation & purification / Q000493:pharmacokinetics; D014018:Tissue Distribution
D019275:Radiopharmaceuticals; D011933:Reagent Kits, Diagnostic; D017256:Technetium Tc 99m Sestamibi