Engle J W, Lopez-Rodriguez V, Gaspar-Carcamo R E, Valdovinos H F, Valle-Gonzalez M, Trejo-Ballado F, Severin G W, Barnhart T E, Nickles R J, Avila-Rodriguez M A
Department of Medical Physics, University of Wisconsin, B1303 WIMR Cyclotron Labs, 1111 Highland Avenue, Madison, WI 53705, USA.
Appl Radiat Isot. 2012 Aug;70(8):1792-6. doi: 10.1016/j.apradiso.2012.03.030. Epub 2012 Mar 28.
This work describes the production of very high specific activity (66/68)Ga from (nat)Zn(p,n) and (66)Zn(p,n) using proton irradiations between 7 and 16 MeV, with emphasis on (66)Ga for use with common bifunctional chelates. Principal radiometallic impurities are (65)Zn from (p,x) and (67)Ga from (p,n). Separation of radiogallium from target material is accomplished with cation exchange chromatography in hydrochloric acid solution. Efficient recycling of Zn target material is possible using electrodeposition of Zn from its chloride form, but these measures are not necessary to achieve high specific activity or near-quantitative radiolabeling yields from natural targets. Inductively coupled plasma mass spectroscopy (ICP-MS) measures less than 2 ppb non-radioactive gallium in the final product, and the reactivity of (66)Ga with common bifunctional chelates, decay corrected to the end of irradiation, is 740 GBq/μmol (20 Ci/μmol) using natural zinc as a target material. Recycling enriched (66)Zn targets increased the reactivity of (66)Ga with common bifunctional chelates.
这项工作描述了利用 7 至 16 MeV 的质子辐照，通过（天然）锌（p，n）和（66）锌（p，n）反应生产高比活度（66/68）镓的过程，重点是用于常见双功能螯合剂的（66）镓。主要放射性金属杂质是由（p，x）反应产生的（65）锌和由（p，n）反应产生的（67）镓。在盐酸溶液中通过阳离子交换色谱法可实现从靶材料中分离放射性镓。通过从氯化物形式的锌进行电沉积，可以有效地回收锌靶材料，但对于从天然靶材获得高比活度或接近定量的放射性标记产率而言，这些措施并非必需。电感耦合等离子体质谱法（ICP-MS）测得最终产物中无放射性镓含量低于 2 ppb，以天然锌为靶材时，经辐照结束时衰变校正后，（66）镓与常见双功能螯合剂的反应活性为 740 GBq/μmol（20 Ci/μmol）。回收富集的（66）锌靶材提高了（66）镓与常见双功能螯合剂的反应活性。
