Somerville Samuel V, Benedetti Tania M, Ramadhan Zeno R, Yao Yin, Tilley Richard D, Gooding J Justin
School of Chemistry and Australian Centre for NanoMedicine, The University of New South Wales Sydney 2052 Australia
Mark Wainwright Analytical Centre, The University of New South Wales Sydney 2052 Australia.
Chem Sci. 2025 Aug 22. doi: 10.1039/d5sc04268b.
The specificity of enzymes for their substrate typically means there is one enzyme for one molecule. Nanozyme research has focussed on mimicking reactions that enzymes can perform, with far less emphasis on selectively reacting with species in complex biological fluids. Herein we ask the question, can a nanozyme be engineered to do what enzymes cannot do, detect and react selectively with two different substrates in the same blood sample? This is achieved using a nanoparticle that mimics the three-dimensional geometry of an enzyme with isolated substrate channels leading to an active site. The nanoparticle was composed of an active gold core and an inert carbon shell that has nanochannels and was immobilised onto an electrode. With careful choices of electrochemical potential, the solution environment inside the carbon nanochannels can be controlled to create the conditions ideal for selectively reacting with each species in sequence. In this way it was shown that glucose and dopamine could be selectively detected in the same unadulterated whole blood, by using two different electrochemical potential pulse profiles. The concept of using nanoconfinement as enzymes do, altering the solution environment inside channels, and using electrochemical potentials to choose which reactions take place, which enzymes cannot do, is a general principle and can be extended to other active sites and substrates.
酶对其底物的特异性通常意味着一种分子对应一种酶。纳米酶研究主要集中在模拟酶能够进行的反应上，而很少强调与复杂生物流体中的物质进行选择性反应。在此，我们提出一个问题，能否设计一种纳米酶来实现酶无法做到的事情，即在同一血样中对两种不同底物进行选择性检测和反应？这是通过使用一种纳米颗粒实现的，该纳米颗粒模仿了具有通向活性位点的孤立底物通道的酶的三维几何结构。该纳米颗粒由一个活性金核和一个具有纳米通道的惰性碳壳组成，并固定在电极上。通过仔细选择电化学电位，可以控制碳纳米通道内的溶液环境，以创造出依次与每种物质进行选择性反应的理想条件。通过这种方式，利用两种不同的电化学电位脉冲曲线，证明了可以在同一未掺假的全血中选择性地检测葡萄糖和多巴胺。像酶一样利用纳米限域作用来改变通道内的溶液环境，并利用电化学电位来选择发生哪些反应，而这是酶无法做到的，这一概念是一个通用原则，并且可以扩展到其他活性位点和底物。
