Hung J C, Chowdhury S, Redfern M G, Mahoney D W
Nuclear Medicine, Department of Diagnostic Radiology, Mayo Clinic, Rochester, Minnesota, USA.
Eur J Nucl Med. 1997 Jun;24(6):655-9. doi: 10.1007/BF00841404.
The method currently recommended for the preparation of technetium-99m bicisate (99mTc-bicisate) requires a lengthy 30-min incubation at room temperature. The purpose of this study was to evaluate an alternative method to shorten the preparation time. 99mTc-bicisate was prepared with 3.7 GBq (100 mCi) 99mTc according to the manufacturer's instructions, except for the final incubation step, which was replaced with the microwave heating procedure. A standard thin-layer chromatography (TLC) method (i.e., Baker-Flex silica gel IB-F TLC plate with ethyl acetate as mobile phase) was used for the determination of the radiochemical purity (RCP) of 99mTc-bicisate. Our evaluation with different microwave heating processes (300 W with different heating times) demonstrated that as the microwave heating temperature was increased (i.e., 44 masculine-71 masculine C), an increased percentage of samples reached 95% within 5 min post preparation (n=58). The highest RCP value (i.e., 97.4%+/-0.5%, n=10) could be obtained immediately after an 8-s microwave heating time at 300 W (microwave temperature at 69 masculine C), and an average RCP value of 96.4%+/-1.3% (n=90) was maintained throughout the 24-h evaluation period. However, the trend seemed to reverse at higher microwave temperatures (i.e., 76 masculine-90 masculine C), which reconfirmed our initial findings that overheating had no benefit for the preparation of 99mTc-bicisate. To ensure that temperature was the only determining factor, a hot water incubator set at 69 masculine C was used (n=6). Similar RCP results were achieved. In conclusion, the use of a microwave oven at a low heat cycle provides a rapid and efficient way to prepare 99mTc-bicisate.
目前推荐的制备锝-99m双半胱乙酯(99mTc-双半胱乙酯)的方法需要在室温下进行长达30分钟的孵育。本研究的目的是评估一种缩短制备时间的替代方法。按照制造商的说明,用3.7 GBq(100 mCi)的99mTc制备99mTc-双半胱乙酯,但最后一步孵育步骤用微波加热程序代替。采用标准的薄层色谱法(即使用Baker-Flex硅胶IB-F TLC板,以乙酸乙酯为流动相)测定99mTc-双半胱乙酯的放射化学纯度(RCP)。我们对不同微波加热过程(300 W,不同加热时间)的评估表明,随着微波加热温度升高(即44℃-71℃),制备后5分钟内达到95%的样品百分比增加(n = 58)。在300 W下微波加热8秒(微波温度为69℃)后可立即获得最高RCP值(即97.4%±0.5%,n = 10),并且在整个24小时评估期内平均RCP值保持在96.4%±1.3%(n = 90)。然而,在较高微波温度(即76℃-90℃)下趋势似乎相反,这再次证实了我们最初的发现,即过热对99mTc-双半胱乙酯的制备没有益处。为确保温度是唯一的决定因素,使用了设置为69℃的热水培养箱(n = 6)。获得了相似的RCP结果。总之,在低加热周期下使用微波炉为制备99mTc-双半胱乙酯提供了一种快速有效的方法。