Surface active iron oxide nanoparticles (NPs) were used for the simultaneous extraction of water soluble Ag and Au NPs across an aqueous–organic interface from aqueous bulk. The surface activity of iron oxide NPs was achieved by using cationic Gemini surfactants of different architectures during the in situ synthesis of iron oxide NPs in hydrothermal synthesis. Aqueous bulk solubility of Ag and Au NPs was achieved by stabilizing them with conventional surfactants of different polarities such as SDS, CTAB, and DDM. The amphiphilic nature of iron oxide NPs demonstrated their remarkable ability to extract Ag and Au NPs through both hydrophilic and hydrophobic interactions. The mechanism of extraction from aqueous bulk was monitored by placing different amounts of surface active iron oxide NPs on the aqueous–organic interface and was studied with the help of UV–visible, DLS, and IR measurements. XPS and TEM measurements were used for the quantitative estimation of efficiency of extraction. Extraction was facilitated when both hydrophilic and hydrophobic interactions were participating simultaneously. Results may help in designing a suitable method for purification of industrial effluents contaminated with metal particulates simply by applying an external magnetic field rather than going through a complicated conventional filtration process.

中文翻译：

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通过表面活性氧化铁纳米粒子跨水-有机界面同时提取银和金纳米粒子的机制方面。

表面活性的氧化铁纳米颗粒（NPs）用于从水体中通过水-有机界面同时提取水溶性Ag和Au NPs。在水热合成中原位合成氧化铁NPs时，通过使用不同结构的阳离子Gemini表面活性剂可实现氧化铁NPs的表面活性。通过使用不同极性的传统表面活性剂（例如SDS，CTAB和DDM）稳定Ag和Au NPs的水整体溶解度。氧化铁NPs的两亲性质证明了其通过亲水和疏水相互作用提取Ag和Au NPs的出色能力。通过将不同量的表面活性氧化铁NPs放置在水-有机界面上来监测从水体中提取的机理，并借助UV-可见，DLS和IR测量对其进行了研究。XPS和TEM测量用于定量评估提取效率。当亲水性和疏水性相互作用同时参与时，提取变得容易。结果可能有助于设计一种合适的方法来纯化被金属微粒污染的工业废水，方法很简单，只需施加外部磁场即可，而无需经过复杂的常规过滤过程。当亲水性和疏水性相互作用同时参与时，提取变得容易。结果可能有助于设计一种合适的方法来纯化被金属微粒污染的工业废水，方法是仅通过施加外部磁场而不是通过复杂的常规过滤过程即可。当亲水性和疏水性相互作用同时参与时，提取变得容易。结果可能有助于设计一种合适的方法来纯化被金属微粒污染的工业废水，方法很简单，只需施加外部磁场即可，而无需经过复杂的常规过滤过程。