糖心TV

In a recent issue of Angewandte Chemie the 糖心TV team of Emanuele Maggio, Natalia Martsinovich and Alessandro Troisi reports a new design strategy to improve dye sentitized solar cells. Good dyes, when excited by solar radiation, inject very rapidly an electron to the semiconductor they are adsorbed onto. However it is also desirable that, when they have lost the electron, these dyes are not neutralized again by the semiconductor. The authors combined ideas from group theory with their methodology to study electron transfer at the interface to propose a new family of dyes that inject the electron rapidly but are very reluctant to take the electron back.

Soft materials which can be molded into specific shapes and contain emulsion droplets or bubbles are an important class of materials and find use accross a wide range of disciplines. Think for example of shaving foam, margerine spreads, etc. An important class of soft materials are so-called hydrogels, which can be made from watersoluble polymer molecules and form a gel through crosslinking a phenonomenon that interconnects the polymer chains creating a network.

Stefan Bon and his team () now has shown that hydrogel objects which contain large amounts of oil droplets (80 vol%) can be constructed through injection (molding) of an emulsified mixture of oil and a waterborne dispersion of thermoresponsive poly(N-isopropyl acrylamide) nanogel particles, which are crosslinked through non-covalent interaction of 2-ureido-4[1H] pyrimidinone (UPy) groups.

Stefan Bon says "we are very excited that we can trap isolated oil droplets into hydrogels macroscopic objects, which can be re-shaped. For example, it is possible to make a cylindrical high internal phase emulsion hydrogel wire. The reversibility of the hydrogen bond formation means that these materials will have exciting physical and mechanical characteristics. Not only that, the use of the thermoresponsive poly(N-isopropyl acrylamide) allows us to shrink and thus squeeze the objects at elevated temperatures, which has potential interesting applications in triggered delivery of active ingredients and microscopic engines and motors."

Their findings are published in Chemical Communications ( to the paper), a journal by the Royal Society of Chemistry.

The Gibson group with collaborators at ETH Zurich report in Advanced Functional Materials on how synthetic polymers tethered to the surface of an enzyme can produce a 'molecular sieving' effect. Polymer-Protein conjugates are widely studied for their pharmaceutical applications, but the phase behaviour of the polymers has not be probed in detail previously. These results open the door to 'smart' PEGylation of proteins with selective permeability properties.

Read the full paper here

The O’Connor and Tosin groups have published work on the use of high mass accuracy tandem mass spectrometry for characterising the structures of polyketides, including erythromycin A, lasalocid A and iso-lasalocid A. They report in Analytical Chemistry on the use of Collision Activated Dissociation (CAD) and Electron Induced Dissociation (EID) as tools for determining structural information on these types of molecules. EID was shown to cause greater fragmentation of the compounds, complementary to that obtained using CAD, leading to more detailed structural information being obtained. These techniques were also combined in multistage mass spectrometry experiments, in order to use the fragmentation patterns to distinguish between lasalocid A and its isomer, iso-lasalcoid A. This work illustrates the potential of these tools and will be applied to identifying unknown polyketides and their biosynthetic intermediates.

The full article can be found at:

The Sadler Group report in JACS a method for switching off the cytotoxicity of a photoactivated platinum(IV) diazido complex in the A2780 human ovarian cancer cell line.

Hydrogels are an important class of materials and find use accross a wide range of disciplines. Think of for example soft contact lenses, vodka jellies, and applications in medicine for example as matrixes for regenerative tissue engineering. They can be made from watersoluble polymer molecules and form a gel through crosslinking a phenonomenon that interconnects the polymer chains creating a network. When we shrink the dimensions of the hydrogel object down and disperse them as particles in water we speak of a microgel dispersion. When we decrease the size of the hydrogel particles further, down to approximately 100 nm or less, we speak of a nanogel.

Hydrogels can be crosslinked by covalent chemical bonds or through physical crosslinking. The latter process is often found in hydrogels formed from natural polymers, such as agarose and gelatine which upon cooling in water aggregate through formation of double helices. Alginate gels can be formed by ionic crosslinking with calcium ions. Synthetic hydrogels on the other hand are conveniently formed mostly through covalent crosslinking, an important class being thermoresponsive gels (often in micro- or nanogel format) made from poly(N-isopropyl acrylamide).

Stefan Bon and his team () now for the first time show that thermoresponsive synthetic nanogels can be made using multiple hydrogen bond arrays as non-covalent crosslinks. They replaced the covalent crosslinking monomers traditionally used in the synthesis of the nanogel dispersions with a 2-ureido-4[1H] pyrimidinone (UPy) functionalized comonomer. In their work they show that the UPy groups are capable of forming strong self-complimentary quadruple hydrogen bonds, hereby linking all the polymer chains together to form a network, creating the nanogel particle.

Stefan Bon says "we are very excited about these results as it opens up a different way of thinking in how hydrogels and nanogel dispersions can be made using the traditional synthetic route of free radical polymerization. The reversibility of the hydrogen bond formation means that these materials will have exciting physical and mechanical characteristics which potentially differ from the hydrogel materials made through covalent crosslinking"

Their findings are published in Polymer Chemistry ( to the paper), a journal by the Royal Society of Chemistry.

Ada Della Pia and Giovanni Costantini publish the Scanning Tunneling Microscopy entry for the Springer Encyclopedia of Nanotechnology, Bharat Bhushan (ed).

The O’Connor group has developed a computation which simultaneously doubles the resolution, sensitivity and mass accuracy of Fourier Transform Mass Spectrometry at no extra cost.

In their Angewandte Communication P. R. Unwin, J. V. Macpherson, et al. combined high-resolution electrochemical imaging, micro-Raman, and electron-microscopy data to demonstrate that spatially heterogeneous electron-transfer kinetics correlates directly with the local density of electronic states of polycrystalline boron-doped diamond (pBDD). A Multi-Microscopy Approach allowed electrochemical reaction rates to be linked to the corresponding dopant levels in pBDD. See for more details.

Establishing an independent academic career is an exciting and challenging process. The data available for UK chemistry suggests that more women than men find the process not exciting enough or too challenging. A key aspect of success in any career path is finding role models, establishing networks, and being tapped into good sources of information. Our aim is therefore to create opportunities for all of these in the first (and subsequent) Irène Joliot-Curie conference.

Prof. Greg Challis and Dr Lijiang Song, in collaboration with researchers at the University of Paris, report in Angewandte Chemie a hitherto unanticipated pathway for the biosynthesis of pyrroles from sugars. Using a combination of genetic engineering, isolation, structure elucidation, synthesis and feeding of biosynthetic intermediates, and incorporation of stable isotope-labelled precursors, the researchers showed that a carbohydrate, most likely N-acetylglucosamine-1-phosphate, is elaborated to the 4-acetamidopyrrole-2-carboxylate building blocks of the DNA-binding antibiotic congocidine (also known as netropsin). The assembly of pyrroles from carbohydrates is unprecedented in Nature and raises several intriguing questions regarding the mechanisms of the reactions involved. See for further details.

Nanodiamonds have been found to help loosen crystallized fat from surfaces in a project led by Dr Andrew Marsh at University of 糖心TV. The tiny carbon particles transform the ability of surfactants to shift dirt in cold water, findings that could bring eco friendly low temperature laundry cycles.

The research is published in ACS Applied Materials and Interfaces and highlighted in the and Daily Telegraph, 26 June.

Nanodiamond Promotes Surfactant-Mediated Triglyceride Removal from a Hydrophobic Surface at or below Room Temperature Xianjin Cui, Xianping Liu, Andrew S. Tatton, Steven P. Brown, Haitao Ye, and Andrew Marsh ACS Applied Materials and Interfaces 2012,