Integrated nanozymes for brain chemistry

April 13, 2016, Nanjing University

Nanozymes are novel nanomaterials with enzyme mimicking activities, which are superior to natural enzymes and even conventional artificial enzymes. They have attracted considerable attention because they offer the possibility of lowered cost, improved stability, and excellent recyclability. However, the specificity and catalytic activity of current nanozymes are still far lower than that of their natural counterparts, which in turn have limited their broad applications.

To tackle this challenge, Professor Wei and his team from Nanjing University, Nanjing Drum Tower Hospital, and Emory University now report the design and development of integrated nanozymes by confining two cascade catalysts inside a nanostructured metal-organic framework. A major advantage of this integrated design is that the first occurs in nanoscale proximity to the second enzyme, so products of the first reaction can be used immediately as substrates for the second reaction, thus overcoming the problems of diffusion-limited kinetics and product instability.

Specifically, a molecular catalyst (e.g., hemin) and a natural (e.g., glucose oxidase, GOx) have been simultaneously assembled inside a nanoscaled zeolitic imidazolate framework (ZIF-8), and the resulting GOx/hemin@ZIF-8 integrated nanozymes show numerous merits such as enhanced catalytic activity and improved thermal stability. Quantitative enzymatic studies indicate that their integrated nanozymes are able to provide greater than 600 percent enhancement in catalytic activity relative to a simple mixture of hemin@ZIF-8 and GOx@ZIF-8. Their strategy is general and has also been applied to other enzymes (e.g., lactate oxidase/hemin@ZIF-8) and multiple catalysts (e.g., invertase/GOx/hemin@ZIF-8).

More excitingly, this dramatic improvement in has allowed them to construct an integrative detection platform by combining the nanozymes with microdialysis and microfluidic techniques. The platform has been successfully employed for the in vivo monitoring of neurochemicals such as striatum glucose in the brains of living rats following ischemia/reperfusion. Considering the vast numbers of combinations of nanozymes with other artificial enzymes and/or , their current strategy and platform might be extended for a wide range of targets associated with many critical diseases in other living animals and even human beings.

Explore further: Improving catalysis through nanoconcentrator systems

More information: Hanjun Cheng et al. Integrated nanozymes with nanoscale proximity for neurochemical monitoring in living brains , Analytical Chemistry (2016). DOI: 10.1021/acs.analchem.6b00975

Related Stories

Improving catalysis through nanoconcentrator systems

January 13, 2016

A group of scientists at the University of Amsterdam (UvA) has developed a new approach in enhancing catalytic performance. In the current issue of Nature Chemistry they present functionalised, self-assembled nanospheres ...

New insight into enzyme evolution

March 3, 2016

How enzymes - the biological proteins that act as catalysts and help complex reactions occur - are 'tuned' to work at a particular temperature is described in new research from groups in New Zealand and the UK, including ...

Bio-inspired biomimetics can outperform natural coenzymes

February 1, 2016

Researchers from the University of Amsterdam's Van 't Hoff Institute for Molecular Sciences (HIMS) have developed a range of synthetic biomimetic compounds to replace the relatively expensive natural NADH and NADPH coenzymes ...

Recommended for you

Building a better battery, layer by layer

October 15, 2018

A team of researchers from Shinshu University in Nagano, Japan is now closer to a thin, high-capacity lithium-ion battery that could open the door to better energy storage systems for electric vehicles. The research team ...

An RNA key that unlocks innate immunity

October 12, 2018

RNA has long been the neglected middle child of biomolecules, the go-between between DNA, which encodes the cell's instructions, and proteins, which carry them out. Increasingly, though, researchers are recognizing RNA as ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.