Achieving enhanced peroxidase-like activity in multimetallic nanorattles
Achieving enhanced peroxidase-like activity in multimetallic nanorattles
复制标题
在多金属纳米摇铃中实现增强的过氧化物酶样活性
DOI：
10.1039/d2dt02389j
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发表时间：
2022
影响因子：
4
通讯作者：
Camargo, Pedro H.
中科院分区：
文献类型：
--
作者：
da Silva, Flavia G.;Formo, Eric V.;Camargo, Pedro H.
金纳米颗粒（Au NPs）作为人工酶已得到广泛应用，但其性能仍然有限。为了解决这一挑战，我们将重点放在多金属纳米炮上，该纳米炮由双金属AgAu壳内的Au核组成，由空隙隔开（Au@AgAu NRs）。它们是通过电替换方法制备的，并包含一个由AgAu合金组成的超薄多孔外壳。通过使用TMB氧化作为模型转换来研究过氧化物样活性，我们发现NRs的活性相对于传统Au NPs增加了152倍。根据动力学结果，NRs也表现出最低的Km，表明与底物的相互作用更好，产物形成更快。我们还观察到产物浓度与oxTMB之间的线性关系是H2O2浓度的函数，这可以进一步应用于H2O2传感应用（比色检测）。这些数据表明，相对于固体材料，核磁共振材料具有增加表面积的综合效应，暴露高活性表面位点的可能性，以及由于核和壳组分之间的空隙区域而产生的纳米限制效应。这些结果为优化类过氧化物酶的性能提供了重要的见解，超越了传统NPs的性能，并可能激发性能更好的人工酶的开发。
Gold nanoparticles (Au NPs) have been extensively used as artificial enzymes, but their performance is still limited. We address this challenge by focusing on multimetallic nanorattles comprising an Au core inside a bimetallic AgAu shell, separated by a void (Au@AgAu NRs). They were prepared by a galvanic replacement approach and contained an ultrathin and porous shell comprising an AgAu alloy. By investigating the peroxide-like activity using TMB oxidation as a model transformation, we have found an increase of 152 fold in activities for the NRs relative to conventional Au NPs. Based on the kinetics results, the NRs also showed the lowest Km, indicating better interaction with the substrate and faster product formation. We also observed a linear relationship between the concentration of the product and oxTMB as a function of H2O2 concentration, which could be further applied for H2O2 sensing applications (colorimetric detection). These data suggest that the NRs enable the combined effect of an increased surface area relative to solid counterparts, the possibility of exposing highly active surface sites, and the exploitation of nanoconfinement effects due to the void regions between the core and shell components. These results provide important insights into the optimization of peroxidase-like performances beyond what can be achieved in conventional NPs and may inspire the development of better-performing artificial enzymes.