News
Inorganic Materials book series
The fifth volume, Energy Materials, co-edited by Richard Walton, with Duncan Bruce (York) and Dermot O’Hare (Oxford), has been published this week by Wiley.
http://eu.wiley.com/WileyCDA/WileyTitle/productCd-0470997524.html
Zirconium catalysts not dead, just resting.
Dormant polymerization catalysts are given a rude awakening by Giles Theaker, Peter Scott and Warwick Chemistry Alumnus Colin Morton at Infineum. The results indicate how many old catalysts, thought to be dead, are just in a dormant state. The results published in the American Chemical Society journal Macromolecules describe a new mechanism for polymerization of styrenes.
JACS cover for Challis group
Prof. Greg Challis and his team together with Thomson and co-workers feature on this weeks cover of the Journal of the American Chemical Society. The absolute and relative stereochemistry of streptorubin B, a brightly colored prodiginine antibiotic, has been determined. Challis and co-workers utilized a mutant of Streptomyces coelicolor to conduct a mutasynthesis using enantioenriched deuterium-labeled biosynthetic precursors, while Thomson and co-workers developed an enantioselective total synthesis via a 10-membered pyrrolophane intermediate. See Challis and co-workers, p 1793, and Thomson and co-workers, p 1799. View the article.
Understanding Stimuli-Responsive Biomaterials
Matthew Gibson
and collaborators investigate in detail the behaviour of stimuli-responsive polymer-protein conjugates in Polymer Chemistry. It is shown that at in vivo concentrations and when measured in blood rather than water, the behaviour of these materials deviates significantly from what is normally expected.
Konstantinos Bebis, Mathew W. Jones, David M. Haddleton and Matthew I. Gibson*. Polymer Chemistry, 2011, DOI: 10.1039/C0PY00408A
Read how the Bonlab armors polymer vesicles with colloids in JACS
|
The ability of some forms of plankton and bacteria to build an extra natural layer of nanoparticle-like armour has inspired chemists at the University of Warwick to devise a startlingly simple way to give drug bearing polymer vesicles (microscopic polymer based sacs of liquid) their own armoured protection. The Warwick researchers have been able to decorate these hollow structures with a variety of nanoparticles opening a new strategy in the design of vehicles for drug release, for example by giving the vesicle “stealth” capabilities which can avoid the body’s defences while releasing the drug. Advances in polymerisation have led to a surge in the creation of vesicles made from polymer molecules. Such vesicles have interesting chemical and physical properties which makes these hollow structures potential drug delivery vehicles. The University of Warwick team were convinced that even more strength, and interesting tailored properties, could be given to the vesicles if they could add an additional layer of colloidal armour made from a variety of nanoparticles.
“We took our inspiration from nature, in how it adds protection and mechanical strength in certain classes of cells and organisms. In addition to the mechanical strength provided by the cytoskeleton of the cell, plants, fungi, and certain bacteria have an additional cell wall as outermost boundary. Organisms that particularly attracted our interest were those with a cell wall composed of an armour of colloidal objects – for instance bacteria coated with S-layer proteins, or phytoplankton, such as the coccolithophorids, which have their own CaCO3-based nano-patterned colloidal armour” The Warwick researchers hit on a surprisingly simple and highly effective method of adding a range of different types of additional armour to the polymer based vesicles. One of those armour types was a highly regular packed layer of microscopic polystyrene balls. This configuration meant the researchers could design a vesicle which had an additional and precise permeable reinforced barrier for drug release, as a result of the crystalline-like ordered structure of the polystyrene balls. The researchers also succeeded in using the same technique to add a gelatine-like polymer to provide a “stealth” armour to shield vesicles from unwanted attention from the body’s immune system while it slowly released its drug treatment. This particular coating (a poly((ethyl acrylate)-co-(methacrylic acid)) hydrogel) absorbs so much surrounding water into its outer structure that it may be able to fool the body’s defence mechanism into believing it is in fact just water.
The research has just been published in a paper entitled Polymer Vesicles with a Colloidal Armor of Nanoparticles by Rong Chen, Daniel J. G. Pearce, Sara Fortuna, David L. Cheung, and Stefan A. F. Bon* Department of Chemistry, University of Warwick in the current Journal of the American Chemical Society http://dx.doi.org/10.1021/ja110359f Note for Editors: The cryo electron microscope used for the research have been funded by the Science City Research Alliance (SCRA) which is part of a larger investment by Advantage West Midlands and ERDF in the research infrastructure of the West Midlands region, which unites the University of Warwick and the University of Birmingham and the in a strategic research partnership – SCRA – formed under the Birmingham Science City initiative. Birmingham Science City, funded by Advantage West Midlands, is a region-wide partnership of public sector, businesses and the research base, which is facilitating the use of science and technology to improve the quality of life and prosperity of the West Midlands. For further information please contact: Peter Dunn, Head of Communications, Communications Office, PR10 31st January 2011 |
|
Dr Jósef Lewandowski joins Warwick Chemistry
We are delighted to announce that Dr Jósef Lewandowski will be joining us as Assistant Professor in Physical Chemistry from 1 September 2011.
Dr Lewandowski's research interests are primarily in the area of solid state NMR.
Jósef comes to us from the European Center for high Field NMR in Lyon, France where he is currently completing a postdoctoral stay with Prof Lyndon Emsley.
Walton group's research highlighted on the front cover of Journal of Applied Crystallography
Recent work by the group of Richard Walton in collaboration with the group of Professor Pam Thomas of the Department of Physics at Warwick (Lethbridge et al. J. Appl. Crystallogr. 43 (2010) 168-175 ) has been selected as the cover image for the Journal of Applied Crystallography for 2011. The research involved the synthesis of usually large crystals of microporous zeolites, whose behaviour on heating and cooling was then examined using birefringence microscopy. This allowed new insights into the materials’ stability and structure as a function of temperature, including the migration of organic guest species through their structures.
Rachel O'Reilly and Andrew Dove guest edit themed issue of Polymer Chemistry
Rachel O'Reilly and Andrew Dove introduce the first themed issue of the journal Polymer Chemistry by the RSC (Royal Society of Chemistry) as guest Editors. The issue contains 2 reviews, 4 communications and 18 full papers of work by emerging investigators in the area of polymer chemistry. You can read this special issue of the journal here.
Scott Group detects chiral building blocks for new materials
Pairs of building blocks are shown using spectroscopic and electrochemical techniques to associate in solution before forming new types of charge transfer material relevant to the search for chiral conductors. The work forms part of the PhD research by former Warwick Postgraduate Research Fellow, Dr Nikola Chmel.
read the paper: http://dx.doi.org/10.1039/C0DT01184C
Shipman and Walsh groups report new method to quantify strength of hydrogen-bonds
Mike Shipman, Tiffany Walsh and co-workers have recently published a new method for detecting and quantifying noncovalent interactions. They have discovered that the rate of nitrogen inversion in aziridine derivatives is dependent on intramolecular interactions between attached functional groups. For example, the ortho-substituted pyridine undergoes faster inversion than its para-substituted analogue as a result of the formation of an intramolecular amide–pyridine (NH⋅⋅⋅N) hydrogen bond in the transition state (see graphic). Using simple NMR methods, it is possible to quantify the strength of these interactions in the transition state, and compare them with those predicted using computational methods. This work is expected to have applicability to a range of other important noncovalent interactions. It was conducted in collaboration with the Tucker group at the University of Birmingham.
The paper is published in the 17 January 2011 issue of Angewandte Chemie.
http://onlinelibrary.wiley.com/doi/10.1002/anie.201005580/abstract
'Hot Article' In Chemical Communications from Walton Group
Richard Walton and his collaborators at the University of Versailles, France, have recently published a paper in Chemical Communications that reports the unusual hydration behaviour of a metal-organic framework material. The highly flexible structure undergoes a spontaneous expansion upon hydration to give a crystalline phase containing inifinite tubes of hydrogen-bonded water molecules. The hydration is completely reversible as shown by time-resolved X-ray diffraction. The work made use of high-resolution X-ray diffraction at the European Synchrotron Radiation Facility in Grenoble, and time-resolved powder X-ray diffraction in Warwick and forms part of a bigger project examining the flexibility of these materials as hosts for sorption and separation of a variety of molecules.
The paper is published in the 14 January 2011 issue of Chemical Communications and highlighted as a Hot Article by the publishers.
http://xlink.rsc.org/?doi=C0CC03882B
http://blogs.rsc.org/cc/2010/12/14/hot-article-round-up-for-november/
Platinum and Blue Light Combine to Combat Cancer
When it comes to health care blue lights, are usually most useful on the top of ambulances but now new research led by the University of Warwick has found a way to use blue light to activate what could be a highly potent platinum-based cancer treatment.
Research led by the University of Warwick, along with researchers from Ninewells Hospital Dundee, and the University of Edinburgh, have found a new light-activated platinum-based compound that is up to 80 times more powerful than other platinum-based anti-cancer drugs and which can use “light activation” to kill cancer cells in a much more targeted way than similar treatments.
The University of Warwick team had already found a platinum-based compound that they could activate with ultra-violet light but that narrow wave length of light would have limited its use. Their latest breakthrough has discovered a new platinum based compound known as trans,trans,trans-[Pt(N3)2(OH)2(py)2] that can be activated by normal visible blue, or even green, light. It is also stable and easy to work with, and it is water soluble so it can simply dissolve and be flushed out of the body after use.
The University of Warwick researchers passed the new compound to colleagues at Ninewells Hospital Dundee, who tested it on oesophageal cancer cells cultivated within lab equipment. Those tests show that once activated by blue light the compound was highly effective requiring a concentration of just 8.4 micro moles per litre to kill 50% of the cancer cells. The researchers are also beginning to examine the compound’s effectiveness against ovarian and liver cancer cells. Early results there are also excellent but that testing work is not yet complete.
Professor Peter Sadler, from the Department of Chemistry from University of Warwick, who led the research project, said:
“This compound could have a significant impact on the effectiveness of future cancer treatments. Light activation provides this compound’s massive toxic power and also allows treatment to be targeted much more accurately against cancer cells.”
“The special thing about our complex is that it is not only activated by ultra-violet light, but also by low doses of blue or green light. Light activation generates a powerful cytotoxic compound that has proven to be significantly more effective than treatments such as cisplatin.”
We believe that photoactivated platinum complexes will make it possible to treat cancers that have previously not reacted to chemotherapy with platinum complexes,” says Sadler. “Tumors that have developed resistance to conventional platinum drugs could respond to these complexes and with less side-effects.”
This research has been supported by the EPSRC, MRC, ERC and Science City (ERDF/AWM).
Note for editors: The research has just been published in Angewandte Chemie, under the title “A Potent Trans Diimine Platinum Anticancer Complex Photoactivated by Visible Light”. The authors are – Project leader Professor Peter Sadler, (University of Warwick) and Nicola J. Farrer, Julie A. Woods, Luca Salassa, Yao Zhao, Kim S. Robinson, Guy Clarkson, and Fiona S. Mackay.
For more information please contact:
Professor Peter Sadler
University of Warwick, Department of Chemistry
Tel: +44 (0)7913 944357
P.J.Sadler@warwick.ac.uk
Peter Dunn, Head of Communications, University of Warwick,
44 (0)24 76 523708
mobile/cell +44 (0)7767 655860
p.j.dunn@warwick.ac.uk
PR171 9th December 2010