Steinberg Spencer, Hodge Vernon, Schumacher Brian, Sovocool Wayne
Department of Chemistry, University of Nevada, Las Vegas, NV, 89154-4003, USA.
National Exposure Research Laboratory, United States Environmental Protection Agency, Las Vegas, NV, 89119,, USA.
Environ Monit Assess. 2017 Mar;189(3):99. doi: 10.1007/s10661-017-5809-6. Epub 2017 Feb 7.
Amendment of a carbon paste electrode consisting of graphite and Nujol®, with a variety of organic and inorganic materials, allows direct adsorption of silver nanoparticles (AgNPs) from aqueous solution in either open or close circuit modes. The adsorbed AgNPs are detected by stripping voltammetry. Detection limits of less than 1 ppb Ag are achievable with a rotating disk system. More than one silver peak was apparent in many of the stripping voltammograms. The appearance of multiple peaks could be due to different species of silver formed upon stripping or variation in the state of aggregation or size of nanoparticles. With most of these packing materials, dissolved Ag was also extracted from aqueous solution, but, with a packing material made with Fe(II,III) oxide nanoparticles, only AgNPs were extracted. Therefore, it is the best candidate for determination of metallic AgNPs in aqueous environmental samples without interference from Ag.
由石墨和微晶蜡制成的碳糊电极，通过添加各种有机和无机材料进行改性后，能够在开路或闭路模式下直接从水溶液中吸附银纳米颗粒（AgNPs）。吸附的AgNPs通过溶出伏安法进行检测。使用旋转圆盘系统可实现低于1 ppb Ag的检测限。在许多溶出伏安图中，出现了不止一个银峰。多个峰的出现可能是由于溶出时形成了不同种类的银，或者是纳米颗粒的聚集状态或尺寸发生了变化。使用大多数这些填充材料时，也能从水溶液中萃取溶解的Ag，但使用由铁（II,III）氧化物纳米颗粒制成的填充材料时，仅能萃取AgNPs。因此，它是测定水性环境样品中金属AgNPs的最佳选择，不会受到Ag的干扰。
