Li Weijia, Li Chunsheng, Zhao Jiujiang, Cornett R Jack
Radiation Protection Bureau, Health Canada, A.L.:6302D1, 775 Brookfield Rd, Ottawa, ON, K1A 1C1, Canada. weijia
Anal Chim Acta. 2007 May 29;592(1):106-13. doi: 10.1016/j.aca.2007.04.012. Epub 2007 Apr 19.
The diffusive gradients in thin films technique (DGT) was used for uranium measurements in water. DGT devices with Dowex resin binding phase (Dow DGT) were tested in synthetic river water, which gave 84% response to total uranium concentration. The devices were also deployed in natural river water and compared to devices with other types of binding phases, Chelex 100 resin beads imbedded in polyacrylamide hydrogel (Chelex DGT) and DE 81 anion exchange membrane (DE DGT), deployed in the same location at the same time. The measurement by Dow DGT was the lowest among the different types of the DGT devices, 45% of total uranium, while measurement by DE DGT was the highest, 98% of total uranium. The results achieved by the three types of DGT devices were explained by three DGT working mechanisms, equilibrium between complexes of resin/uranyl carbonates and complexes of resin/competitive ligands in water, effective reduction of uranyl carbonate concentration by the binding phase and dissociation of UO2(CO3)2(2-) and UO2(CO3)3(4-) within the diffusive layer in a DGT device. It is hoped that by deploying the DGT devices with different binding phases in natural waters, additional information on uranium speciation could be obtained.
薄膜扩散梯度技术（DGT）用于水中铀的测量。采用具有Dowex树脂结合相的DGT装置（Dow DGT）在合成河水中进行测试，其对总铀浓度的响应率为84%。这些装置还部署在天然河水中，并与同时在同一地点部署的具有其他类型结合相的装置进行比较，即嵌入聚丙烯酰胺水凝胶中的Chelex 100树脂珠（Chelex DGT）和DE 81阴离子交换膜（DE DGT）。在不同类型的DGT装置中，Dow DGT的测量值最低，为总铀的45%，而DE DGT的测量值最高，为总铀的98%。三种类型的DGT装置所获得的结果可以通过三种DGT工作机制来解释，即树脂/碳酸铀酰络合物与水中树脂/竞争性配体络合物之间的平衡、结合相对碳酸铀酰浓度的有效降低以及DGT装置扩散层内UO2(CO3)2(2-)和UO2(CO3)3(4-)的解离。希望通过在天然水体中部署具有不同结合相的DGT装置，可以获得有关铀形态的更多信息。
