Surface decoration of gold nanoparticles (AuNPs) effectively improves the stability and sensitivity of a traditional AuNP-based lateral flow immunoassay (LFIA). AuNPs decorated with citric acid, tannic acid, polydopamine, and polyethylene glycol (PEG) have been reported. However, these prepared nanoparticles have yet to be compared with each other in the same analytical system. Here, we synthesized stabilized AuNPs decorated with these four ligands and explored their properties to enhance the stability and sensitivity of LFIA. The results revealed that AuNPs@PEG was the optimal signal probe with an average AuNP diameter of 30 nm. It demonstrated significant advantages in tolerating extreme conditions (concentration of NaCl at 0.34 M) and improved sensitivity (twofold better than traditional LFIA). AuNPs@PEG-based LFIA showed cut-off values of 20–20,000 μg/kg for 18 sulfonamides and 1.6–200 μg/kg for antibacterial synergists in chicken meat, and the corresponding limits of detection were 2.0–548.2 μg/kg and 0.2–9.5 μg/kg. In conclusion, we are the first to investigate the properties of four stabilized AuNPs, and AuNPs@PEG shows good promise for use in LFIA.

中文翻译：

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使用稳定的 AuNP 提高侧流免疫分析的稳定性和灵敏度，同时检测鸡肉中的磺胺类药物和抗菌增效剂

金纳米颗粒 (AuNP) 的表面修饰有效提高了传统基于 AuNP 的侧流免疫分析 (LFIA) 的稳定性和灵敏度。已经报道了用柠檬酸、单宁酸、聚多巴胺和聚乙二醇（PEG）修饰的金纳米粒子。然而，这些制备的纳米颗粒尚未在同一分析系统中进行相互比较。在这里，我们合成了用这四种配体修饰的稳定金纳米粒子，并探索了它们增强 LFIA 稳定性和灵敏度的特性。结果表明，AuNPs@PEG 是最佳信号探针，平均 AuNP 直径为 30 nm。它在耐受极端条件（氯化钠浓度为 0.34 M）和提高灵敏度（比传统 LFIA 好两倍）方面表现出显着优势。基于 AuNPs@PEG 的 LFIA 显示鸡肉中 18 种磺胺类药物的截止值为 20-20,000 μg/kg，抗菌增效剂的截止值为 1.6-200 μg/kg，相应的检测限为 2.0-548.2 μg/kg 和 0.2 –9.5微克/千克。总之，我们是第一个研究四种稳定 AuNPs 特性的人，AuNPs@PEG 在 LFIA 中显示出良好的应用前景。