Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, People's Republic of China.
Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, School of Chemistry and Chemical Engineering, Shihezi University, Xinjiang, People's Republic of China.
Int J Nanomedicine. 2018 Mar 9;13:1411-1424. doi: 10.2147/IJN.S149079. eCollection 2018.
Biosynthesis of noble metallic nanoparticles (NPs) has attracted significant interest due to their environmental friendly and biocompatible properties.
In this study, we investigated syntheses of Au, Ag and Au-Ag bimetallic NPs using protein extracts of , which demonstrated powerful metal-reducing ability. The obtained NPs were characterized and analyzed by various spectroscopy techniques.
The protein extract-mediated silver nanoparticles (Drp-AgNPs) were preferably monodispersed and stably distributed compared to protein extract-mediated gold nanoparticles (Drp-AuNPs). Drp-AgNPs and Drp-AuNPs exhibited spherical morphology with average sizes of 37.13±5.97 nm and 51.72±7.38 nm and zeta potential values of -18.31±1.39 mV and -15.17±1.24 mV at pH 7, respectively. The release efficiencies of Drp-AuNPs and Drp-AgNPs measured at 24 h were 3.99% and 18.20%, respectively. During the synthesis process, Au(III) was reduced to Au(I) and further to Au(0) and Ag(I) was reduced to Ag(0) by interactions with the hydroxyl, amine, carboxyl, phospho or sulfhydryl groups of proteins and subsequently stabilized by these groups. Some characteristics of Drp-AuNPs were different from those of Drp-AgNPs, which could be attributed to the interaction of the NPs with different binding groups of proteins. The Drp-AgNPs could be further formed into Au-Ag bimetallic NPs via galvanic replacement reaction. Drp-AuNPs and Au-Ag bimetallic NPs showed low cytotoxicity against MCF-10A cells due to the lower level of intracellular reactive oxygen species (ROS) generation than that of Drp-AgNPs.
These results are crucial to understand the biosynthetic mechanism and properties of noble metallic NPs using the protein extracts of bacteria. The biocompatible Au or Au-Ag bimetallic NPs are applicable in biosensing, bioimaging and biomedicine.
由于具有环境友好和生物相容性，生物合成贵金属纳米粒子（NPs）引起了人们的极大兴趣。
在这项研究中，我们使用具有强大金属还原能力的 蛋白提取物来研究 Au、Ag 和 Au-Ag 双金属 NPs 的合成。通过各种光谱技术对所得到的 NPs 进行了表征和分析。
与 蛋白提取物介导的金纳米颗粒（Drp-AuNPs）相比， 蛋白提取物介导的银纳米颗粒（Drp-AgNPs）更优选地呈单分散且稳定分布。Drp-AgNPs 和 Drp-AuNPs 呈球形形态，平均粒径分别为 37.13±5.97nm 和 51.72±7.38nm，在 pH7 时的 zeta 电位值分别为-18.31±1.39mV 和-15.17±1.24mV。在 24 小时时测量的 Drp-AuNPs 和 Drp-AgNPs 的释放效率分别为 3.99%和 18.20%。在合成过程中，Au（III）通过与蛋白质的羟基、胺基、羧基、磷酸或巯基相互作用被还原为 Au（I），进一步还原为 Au（0），Ag（I）被还原为 Ag（0），并随后由这些基团稳定。Drp-AuNPs 的一些特性与 Drp-AgNPs 的特性不同，这可能归因于 NPs 与蛋白质的不同结合基团的相互作用。Drp-AgNPs 可以通过电置换反应进一步形成 Au-Ag 双金属 NPs。由于细胞内活性氧（ROS）的产生水平低于 Drp-AgNPs，因此 Drp-AuNPs 和 Au-Ag 双金属 NPs 对 MCF-10A 细胞表现出低细胞毒性。
这些结果对于使用细菌的蛋白质提取物理解贵金属 NPs 的生物合成机制和特性至关重要。具有生物相容性的 Au 或 Au-Ag 双金属 NPs 可应用于生物传感、生物成像和生物医学领域。
