Chemical Science Blog

Scientists in France have combined homogeneous catalysis and atomic force microscopy to create intricate surface patterns.

Atomic Force Microscopy (AFM) works by dragging a sharp tip across a material’s surface to map nanoscale surface topologies or measure surface interactions. Innovations in the design of AFM tips have allowed AFM to become a tool, not only for reading, but also for writing onto surfaces, analogous to creating tattoos on a molecular scale.

To date, AFM tips have only been able to use a narrow range of chemical transformations, including heterogeneous catalysis, to create patterns on a surface.

Now, Jean-Luc Parrain, Sylvain Clair, Olivier Chuzel and colleagues from Aix Marseille University and the National Centre for Scientific Research (CNRS), have attached a homogeneous catalyst to a commercially available AFM probe and used it to carry out…

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Read the original journal article in Chemical Science:
Grafting a homogeneous transition metal catalyst onto a silicon AFM probe: a promising strategy for chemically constructive nanolithography
Dmitry A. Valyaev, Sylvain Clair, Lionel Patrone, Mathieu Abel, Louis Porte, Olivier Chuzel and Jean-Luc Parrain  
Chem. Sci., 2013, 4, 2815-2821
DOI: 10.1039/C3SC50979F

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Scientists in Australia are closer to harvesting hydrogen from two of the most abundant and naturally occurring resources in our environment – seawater and sunlight.

Water oxidation, the first part of the water splitting reaction that can produce hydrogen, is difficult as it is so kinetically unfavourable. Using photocatalysts to overcome this energy barrier is appealing as sunlight can supply the required energy rather than needing electrical or thermal energy.

Unlike some photocatalytic water oxidation methods that use catalysts mounted on a semiconductor to form an electrode, a team, led by Jun Chen and Gerhard Swiegers, from the University of Wollongong, Australia, have shown that…

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Read the original journal article in Chemical Science:
A light-assisted, polymeric water oxidation catalyst that selectively oxidizes seawater with a low onset potential
Jun Chen, Pawel Wagner, Lei Tong, Danijel Boskovic, Weimin Zhang, David Officer, Gordon G. Wallace and Gerhard F. Swiegers  
Chem. Sci., 2013, 4, 2797-2803
DOI: 10.1039/C3SC50812A

Research published in Chemical Science describes the design of a new fluorescent probe that can sense ‘mobile’ zinc outside cells by using a targeting peptide that delivers the probe to the extracellular side of the plasma membrane.

Understanding zinc signalling is a significant area of interest in biological studies. Readily-exchangeable or ‘mobile’ zinc is important in human health and has been shown to have a role in the function of the pancreas, prostate and central nervous system. Current fluorescent zinc sensors tend to be based on small molecules that readily diffuse across cell membranes to give information on zinc in the intracellular environment, but it is difficult to predict how these sensors are distributed beyond the cell membrane where it would be useful to monitor zinc ions released by cells.

Scientists in the United States have developed a design for a zinc sensor that is directed the extracellular plasma membrane by attaching the zinc-signalling fluorophore to a membrane-targeting peptide scaffold. The probes can be readily prepared by solid-phase synthesis to insert the targeting peptide between the fluorophore and a fatty acid that anchors the probe to the cell membrane. The scientists conducted live cell imaging experiments that gave a positive signal for zinc in the plasma membranes of the cells.

Read the ‘HOT’ article for free today:

Peptide-based targeting of fluorescent zinc sensors to the plasma membrane of live cells
Robert J. Radford,a Wen Chyana and Stephen J. Lippard*a
Chem. Sci., 2013, Advance Article, DOI: 10.1039/C3SC50974E