El-Sayed Ramy, Ye Fei, Asem Heba, Ashour Radwa, Zheng Wenyi, Muhammed Mamoun, Hassan Moustapha
Division of Experimental Cancer Medicine (ECM), Department of Laboratory Medicine, Karolinska Institutet, SE-141 86 Stockholm, Sweden.
Division of Functional Materials, KTH Royal Institute of Technology, SE-164 40 Stockholm, Sweden.
Biochem Biophys Res Commun. 2017 Sep 9;491(1):15-18. doi: 10.1016/j.bbrc.2017.07.014. Epub 2017 Jul 4.
We report the studies on origin of peroxidase-like activity for gold nanoparticles, as well as the impact from morphology and surface charge of nanoparticles. For this purpose, we have synthesized hollow gold nanospheres (HAuNS) and gold nanorods (AuNR) with different morphology and surface chemistry to investigate their influence on the catalytic activity. We found that citrate-capped HAuNS show catalyzing efficiency in oxidation reaction of 3,3',5,5'-tetramethylbenzidine (TMB) by hydrogen peroxide (HO) and it is superior to that of cetyltrimethylammonium bromide (CTAB)-capped AuNR. The kinetics of catalytic activities from HAuNS and AuNR were respectively studied under varied temperatures. The results indicated that surface chemistry rather than morphology of nanoparticles plays an important role in the catalytic reaction of substrate. Furthermore, influencing factors such as pH, amount of nanoparticle and HO concentration were also investigated on HAuNS-catalyzed system. The great impact of nanoparticle surface properties on catalytic reactions makes a paradigm in constructing nanozymes as peroxidase mimic for sensing application.
我们报告了关于金纳米颗粒类过氧化物酶活性起源的研究,以及纳米颗粒的形态和表面电荷的影响。为此,我们合成了具有不同形态和表面化学性质的中空金纳米球(HAuNS)和金纳米棒(AuNR),以研究它们对催化活性的影响。我们发现,柠檬酸盐包覆的HAuNS在过氧化氢(HO)氧化3,3',5,5'-四甲基联苯胺(TMB)的反应中表现出催化效率,并且优于十六烷基三甲基溴化铵(CTAB)包覆的AuNR。分别在不同温度下研究了HAuNS和AuNR催化活性的动力学。结果表明,纳米颗粒的表面化学性质而非形态在底物的催化反应中起重要作用。此外,还研究了pH值、纳米颗粒数量和HO浓度等影响因素对HAuNS催化体系的影响。纳米颗粒表面性质对催化反应的巨大影响为构建作为过氧化物酶模拟物用于传感应用的纳米酶提供了范例。