This work reports the synthesis of size-controlled gold nanoparticles as AuNP colloids in aqueous solutions with capping natural polymer matrices – the sodium salt of carboxymethyl cellulose, using a liquid-phase plasma process. The effects of the solution plasma process discharge time, concentrations of gold(III) chloride trihydrate precursor (0.06–2.5 mmol/L) and correlations of the precursor/CMC ratios on the characteristics on the synthesized Au NPs, including size distribution and optical absorption properties, were investigated. The average size (20–90 nm) and form (spherical, hexagonal and triangular) of the AuNPs can be change depending on the initial concentration of Au and the ratios of precursor/CMC on the process synthesis. Gold nanoparticles were used to study a straightforward colorimetric detection of melamine. Melamine caused the AuNPs to agglomerate in aqueous solution, changing their visible color from red to blue. The prepared AuNPs can be used for the detection of melamine with a low LOD and an extremely wide linear range (0.005–0.21 μM.).

中文翻译：

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通过等离子体-液体相互作用合成天然聚合物的金纳米颗粒：基于金纳米颗粒尺寸效应的三聚氰胺的尺寸控制、表征和比色检测

这项工作报告了使用液相等离子体工艺，在水溶液中合成了尺寸受控的金纳米粒子，即 AuNP 胶体，并覆盖天然聚合物基质（羧甲基纤维素的钠盐）。溶液等离子体过程放电时间、三水氯化金(III)前驱体的浓度(0.06–2.5 mmol/L)以及前驱体/CMC比率的相关性对合成Au NPs特性的影响，包括尺寸分布和光学吸收的性质，进行了研究。AuNP 的平均尺寸（20-90 nm）和形状（球形、六角形和三角形）可以根据 Au 的初始浓度和合成过程中前驱体/CMC 的比例而变化。金纳米粒子用于研究三聚氰胺的简单比色检测。三聚氰胺导致金纳米粒子在水溶液中聚集，将其可见颜色从红色变为蓝色。制备的 AuNPs 可用于检测三聚氰胺，具有低 LOD 和极宽的线性范围 (0.005–0.21 μM)。