Traditional radiochemistry approaches for the detection of trace-level alpha-emitting radioisotopes in water require lengthy offsite sample preparations and do not lend themselves to rapid quantification. Therefore, a novel platform is needed that combines onsite purification, concentration, and isotopic screening with a fieldable detection system. This contribution describes the synthesis and characterization of polyamidoxime membranes for isolation and concentration of uranium from aqueous matrices, including high-salinity seawater. The aim was to develop a field portable screening method for the rapid quantification of isotopic distribution by alpha spectroscopy. Membranes with varying degree of modification were prepared by chemical conversion of nitrile groups to amidoxime groups on the surface of polyacrylonitrile ultrafiltration (UFPAN) membranes. Attenuated total reflectance Fourier-transform infrared spectroscopy was used to analyze changes in surface chemistry. Flow through filtration experiments conducted using deionized (DI) water and simulated seawater solutions indicated that the modified membrane was effective in capturing more than 95% of the uranium in the solution prior to breakthrough even in the presence of salt ions. Batch uptake experiments were conducted and compared with the flow through experimental data to elucidate likely binding mechanisms. Alpha spectra of uranium loaded membranes were analyzed, and the effects of solution matrix and degree of modification on peak energy resolution were studied. Peak energy resolutions of 24 ± 2 keV and 32 ± 6 keV full width at half maximum (FWHM) were obtained by loading uranium from DI and seawater solutions onto modified membranes. Full width at 10% maximum of the same spectra were calculated to be 63 ± 9 keV and 160 ± 34 keV to quantify differences seen in peak tailing. Calculations performed based on the results show that it would take less than 3 h of analysis time to screen a sample provided enough volumes of solution are available. This work offers a facile method to prepare polyamidoxime-based membranes for uranium separation and concentration at circumneutral pH values, enabling the rapid, onsite screening of unknown samples.

用于检测水中痕量 α 发射放射性同位素的传统放射化学方法需要长时间的异地样品制备，并且不适合快速量化。因此，需要一个将现场纯化、浓缩和同位素筛选与可现场检测系统相结合的新型平台。该贡献描述了用于从含水基质（包括高盐度海水）中分离和浓缩铀的聚酰胺肟膜的合成和表征。目的是开发一种现场便携式筛选方法，用于通过 α 光谱快速定量同位素分布。通过将聚丙烯腈超滤 (UFPAN) 膜表面上的腈基化学转化为偕胺肟基团，制备了具有不同程度改性的膜。衰减全反射傅里叶变换红外光谱用于分析表面化学的变化。使用去离子 (DI) 水和模拟海水溶液进行的流通过滤实验表明，即使在盐离子存在的情况下，改性膜也能有效地在突破之前捕获溶液中 95% 以上的铀。进行了批量吸收实验，并与通过实验数据的流量进行比较，以阐明可能的结合机制。分析了载铀膜的 α 光谱，研究了溶液基质和改性程度对峰能量分辨率的影响。通过将 DI 和海水溶液中的铀加载到改性膜上，获得了 24 ± 2 keV 和 32 ± 6 keV 的半峰全宽 (FWHM) 的峰值能量分辨率。计算相同光谱的最大 10% 处的全宽为 63 ± 9 keV 和 160 ± 34 keV，以量化峰拖尾中的差异。根据结果​​进行的计算表明，只要有足够体积的溶液可用，筛选样品所需的分析时间不到 3 小时。这项工作提供了一种简便的方法来制备基于聚酰胺肟的膜，用于在中性 pH 值下进行铀分离和浓缩，从而能够快速、现场筛选未知样品。通过将 DI 和海水溶液中的铀加载到改性膜上，获得了 24 ± 2 keV 和 32 ± 6 keV 的半峰全宽 (FWHM) 的峰值能量分辨率。计算相同光谱的最大 10% 处的全宽为 63 ± 9 keV 和 160 ± 34 keV，以量化峰拖尾中的差异。根据结果​​进行的计算表明，只要有足够体积的溶液可用，筛选样品所需的分析时间不到 3 小时。这项工作提供了一种简便的方法来制备基于聚酰胺肟的膜，用于在中性 pH 值下进行铀分离和浓缩，从而能够快速、现场筛选未知样品。通过将 DI 和海水溶液中的铀加载到改性膜上，获得了 24 ± 2 keV 和 32 ± 6 keV 的半峰全宽 (FWHM) 的峰值能量分辨率。计算相同光谱的最大 10% 处的全宽为 63 ± 9 keV 和 160 ± 34 keV，以量化峰拖尾中的差异。根据结果​​进行的计算表明，只要有足够体积的溶液可用，筛选样品所需的分析时间不到 3 小时。这项工作提供了一种简便的方法来制备基于聚酰胺肟的膜，用于在中性 pH 值下进行铀分离和浓缩，从而能够快速、现场筛选未知样品。计算相同光谱的最大 10% 处的全宽为 63 ± 9 keV 和 160 ± 34 keV，以量化峰拖尾中的差异。根据结果​​进行的计算表明，只要有足够体积的溶液可用，筛选样品所需的分析时间不到 3 小时。这项工作提供了一种简便的方法来制备基于聚酰胺肟的膜，用于在中性 pH 值下进行铀分离和浓缩，从而能够快速、现场筛选未知样品。计算相同光谱的最大 10% 处的全宽为 63 ± 9 keV 和 160 ± 34 keV，以量化峰拖尾中的差异。根据结果​​进行的计算表明，只要有足够体积的溶液可用，筛选样品所需的分析时间不到 3 小时。这项工作提供了一种简便的方法来制备基于聚酰胺肟的膜，用于在中性 pH 值下进行铀分离和浓缩，从而能够快速、现场筛选未知样品。