Abstract

The aqueous solution with iron nanoparticles investigated by a microwave stripline sensor based on the optimized double quadratic-shape design. Due to real-time near-field electromagnetic interaction between microwaves and sample S₁₁ reflection coefficient of the sensor was changed depending on iron nanoparticles concentration in the aqueous solution at resonant frequencies. In this work we examined the iron nanoparticles concentration in the 0–20 µg/L concentration range at an operating frequency of about 1.7 GHz. The measured minimum detectable signal was 0.035 dB/(µg/L) and 0.25 MHz/(µg/L) and the measured minimum detectable concentration was 1.4 µg/L and 0.2 µg/L, respectively. The microwave response of sensor systems can be explained by the additional structural changes of water clusters due to the metal nanoparticles ablation. This implemented method has approachable development process and the accuracy of measurement is high, thus it can be applied as a physiochemical sensor for non-invasive monitoring of metal nanoparticles in complex liquids.

中文翻译：

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微波传感器检测水溶液中的铁纳米颗粒

摘要

微波带状线传感器根据优化的二次方二次形设计研究了含铁纳米颗粒的水溶液。由于微波和样品S ₁₁之间的实时近场电磁相互作用传感器的反射系数根据共振频率下水溶液中铁纳米颗粒的浓度而变化。在这项工作中，我们在约1.7 GHz的工作频率下检查了0-20 µg / L浓度范围内的铁纳米颗粒浓度。测得的最小可检测信号为0.035 dB /（μg/ L）和0.25 MHz /（μg/ L），测得的最小可检测浓度分别为1.4μg/ L和0.2μg/ L。传感器系统的微波响应可以通过金属纳米粒子烧蚀引起的水团簇的其他结构变化来解释。该实施方法开发过程平易近人，测量精度高，因此可作为一种物理化学传感器，用于无创监测复杂液体中的金属纳米颗粒。