Many metal nanoparticles are reported to have intrinsic enzyme-like activities and offer great potential in chemical and biomedical applications. In this study, PtCu alloy nanoparticles (NPs), synthesized through hydrothermal treatment of Cu2+ and Pt2+ in an aqueous solution, were evaluated for ferroxidase-like and antibacterial activity. Electron spin resonance (ESR) spectroscopy and colorimetric methods were used to demonstrate that PtCu NPs exhibited strong ferroxidase-like activity in a weakly acidic environment and that this activity was not affected by the presence of most other ions, except silver. Based on the color reaction of salicylic acid in the presence of Fe3+, we tested the ferroxidase-like activity of PtCu NPs to specifically detect Fe2+ in a solution of an oral iron supplement and compared these results with data acquired from atomic absorption spectroscopy and the phenanthroline colorimetric method. The results showed that the newly developed PtCu NPs detection method was equivalent to or better than the other two methods used for Fe2+ detection. The antibacterial experiments showed that PtCu NPs have strong antibacterial activity against Staphylococcus aureus and Escherichia coli. Herein, we demonstrate that the peroxidase-like activity of PtCu NPs can catalyze H2O2 and generate hydroxyl radicals, which may elucidate the antibacterial activity of the PtCu NPs against S. aureus and E. coli. These results showed that PtCu NPs exhibited both ferroxidase- and peroxidase-like activity and that they may serve as convenient and efficient NPs for the detection of Fe2+ and for antibacterial applications.

中文翻译：

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PtCu合金纳米颗粒的类铁氧化物酶和抗菌活性。

据报道，许多金属纳米颗粒具有固有的酶样活性，并在化学和生物医学应用中具有巨大潜力。在这项研究中，评估了通过水溶液中Cu2 +和Pt2 +的水热处理合成的PtCu合金纳米颗粒（NPs）的类铁氧化物酶和抗菌活性。电子自旋共振（ESR）光谱和比色法用于证明PtCu NP在弱酸性环境中表现出强的类似铁氧化酶的活性，并且该活性不受除银以外的大多数其他离子的影响。根据水杨酸在Fe3 +存在下的显色反应，我们测试了PtCu NP的铁氧化酶样活性，以特异性检测口服铁补充剂溶液中的Fe2 +，并将这些结果与从原子吸收光谱法和菲咯啉比色法获得的数据进行了比较。结果表明，新开发的PtCu NPs检测方法与Fe2 +检测中使用的其他两种方法相当或更好。抗菌实验表明，PtCu NPs对金黄色葡萄球菌和大肠杆菌具有很强的抗菌活性。在本文中，我们证明了PtCu NPs的过氧化物酶样活性可以催化H2O2并产生羟基自由基，这可以阐明PtCu NPs对金黄色葡萄球菌和大肠杆菌的抗菌活性。