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11th International Conference on Materials Chemistry (MC11)– Registration now open!

20 Mar 2013

We are delighted to announce that registration for the 11^th International Conference on Materials Chemistry (MC11) is now open.

Why take part in this conference?

In the 20th year of this international Materials Chemistry conference series, this meeting will bring together researchers from across this exciting field to discuss four key areas of application of materials chemistry:

Energy Materials – including all aspects of Materials Chemistry related to energy generation, conversion and storage.
Environmental Materials – the design, synthesis and applications of materials that facilitate processes to provide a sustainable environment.
Biomaterials – materials for tissue engineering and healthcare, green biomaterials and advanced synthesis methods of biomaterials.
Electronic, Magnetic and Optical Materials – encompassing inorganic, organic, hybrid and nano materials, soft matter and interfaces.

Registering early guarantees you an early bird discount of £50 – so register now! And you can showcase your own work by presenting a poster.

MC11 will appeal to academic and industrial scientists working on the chemistry, physics and materials science of functional materials. Come and hear the best in the field and take advantage of many opportunities for discussion with other researchers in materials chemistry.

For more information visit: http://rsc.li/mc11

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If you like it, then you should put two rings on it

19 Mar 2013

Microring resonators are pretty amazing things, offering label-free biosensing by coupling with light and then circulating the photons inside the cavity of the ring, enhancing the interaction between the light and the analytes.

However, I like to think of traditional microring resonators as tents: difficult to construct. They require a submicrometer gap between the input waveguide and the resonator ring structure to allow the coupling of light and before you can even get to that stage, you need to make the microring resonator, which requires a series of complex fabrication steps (FIG 1a). In this Communication, which is part of ChemComm‘s Microfluidics themed web collection, Professor Jonathan Cooper and his colleagues at Glasgow University and at the International Islamic University Malaysia’s CTS Department have made (what I think of as) the double pop-up tent equivalent– or as they call it, the dual disk resonator (DDR). Made from SU8, an epoxy-based polymer used in microfluidics chips, it can be patterned in a single lithographic step. Not only that, but the DDR uses a gapless design and two rings, increasing the sensitivity of the device (FIG 1b).

FIG 1: The hard way or the easy way (a) the traditional microring resonator with submicrometer gap (b) gapless dual disk resonator

Once they had constructed the DDR, the team characterised the optical sensitivity of the device using sucrose solutions to vary the refractive index of the sample above the waveguide. They then went on to show that the sensor could be used to evaluate the dynamics of antibody interactions on surfaces, exploring avidin-biotin-based immobilisations; sharp resonance shifts confirmed the assembly and disassembly of constructs.

The simpler fabrication shows great promise, as the authors suggest that the sensitivity of the device could be greatly improved by coupling more disks to it– in which case Beyoncé might soon be singing ‘if you like it, then you should put a chain on it.’

Read this ‘HOT’ ChemComm article today:

Polymer dual ring resonators for label-free optical biosensing using microfluidics

Muhammad H. M. Salleh, Andrew Glidle, Marc Sorel, Julien Reboud and Jonathan M. Cooper

Chem. Commun., 2013, Advance Article

DOI: 10.1039/C3CC38228A

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Harnessing enzyme-substrate specificity for gel-based sensors

16 Mar 2013

Gels that are held together by non-covalent interactions are a hot topic in supramolecular chemistry. In this Communication, Itaru Hamachi’s research group from Kyoto University report a series of glycolipids that form yellow hydrogels from orange suspensions when heated. The gelation and hence the colour change is reversible, and the authors hoped to use this response to create a sensor system.

Hamachi's gelator molecules

Once the gel has formed, adding a glycosidase enzyme which can selectively cleave the β-glucosidic bond leads to breakup of the gel and a colour change from yellow to orange. This response is only observed with an enzyme that is complimentary to the saccharide used as a “substrate unit” in the gelator. Hence, the authors have harnessed natural enzyme-substrate selectivity to yield a highly selective sensing system. The combination of a number of these gels into a sensor array chip yields a system that can simply and rapidly detect and distinguish a range of glycosidase enzymes. The ability to selectively sense these enzymes could have significant application for diagnosing disease and identifying bacterial contamination of drinking water.

Hamichi's sensor array

Read this ‘HOT’ ChemComm article today:

Supramolecular hydrogels based on bola-amphiphilic glycolipids showing color change in response to glycosidases

Rika Ochi, Kazuya Kurotani, Masato Ikeda, Shigeki Kiyonaka and Itaru Hamachi

Chem. Commun., 2013, 49, 2115-2117

DOI: 10.1039/C2CC37908B

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23rd International Symposium: Synthesis in Organic Chemistry

26 Feb 2013

The deadline for submitting poster abstracts for the 23rd International Symposium: Synthesis in Organic Chemistry is fast approaching – 11 March 2013.

The Synthesis in Organic Chemistry conference is the flagship event of the RSC’s Organic Division. This conference will provide an international showcase for the core area of organic chemistry – synthesis – covering all aspects of contemporary organic synthesis and providing a forum for the ever more exciting methodologies and strategies that continue to emerge.

Don’t miss out – reserve your poster presentation space for a chance to showcase your own work, and register early to take advantage of the £50 saving on the standard fee.

Remember too that there are a limited number of bursaries on offer for students and younger members of the RSC in the early stages of their career – worth £150.

Make sure you take the opportunity to join us to hear outstanding speakers across the many themes of the symposium in an extremely stimulating programme of plenary and keynote lectures.

Check out the event website to find out more – http://rsc.li/os23

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A new system for cancer detection

14 Feb 2013

While current cancer-diagnosis methods rely on an invasive biopsy or the detection of cancer-specific biomarkers, South Korean scientists have developed a simple and non-invasive detector for cancer cells that could speed up the early diagnosis of the condition, leading to a greater chance of survival for cancer patients.

Daunomycin interacting cancer cells viewed with fluorescene microscopy

Cancer cells have been found to differ from normal cells in several ways, including the make up of their cell membranes. Cancer-cell membranes have been found to contain more anionic lipids than normal cells, leading to an overall negatively charged cell surface. Yoon-Bo Shim and co-workers from Pusan National University, have exploited this negative surface charge to develop a probe based on daunomycin, an anti-cancer drug that is known to interact strongly with anionic lipids.

Read the full article in Chemistry World.

Read the original journal article:
Cancer cell detection based on the interaction between an anticancer drug and cell membrane components
Chem. Commun., 2013, 49, 1900-1902
DOI: 10.1039/C2CC38235K

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Penny Brothers joins ChemComm as Associate Editor

25 Jan 2013

ChemComm warmly welcomes Professor Penny Brothers (University of Auckland, New Zealand) as a new Associate Editor.

Penny Brothers is now accepting submissions to ChemComm in the areas of porphyrin chemistry, the main group elements and organometallic chemistry. Her current research interests also include the chemistry of new sustainable materials and inorganic medicinal chemistry.

Submit your next top-notch, high-impact Communication to Penny Brother’s Editorial Office.

Biography

Penny Brothers was born and grew up in Auckland, New Zealand, and completed her BSc and MSc(Hons) degrees in chemistry at the University of Auckland. In 1979 she was awarded a Fulbright Fellowship and set off for Stanford University to begin a PhD in chemistry under the supervision of Professor Jim Collman. Her PhD thesis, and much of her subsequent research work, has centered around the chemistry of porphyrin complexes. Professor Penny Brothers

In 1986 she returned to Auckland and spent two years working as a postdoctoral fellow with Professor Warren Roper in the Department of Chemistry, focussing on organometallic chemistry. In 1988 she took up her current academic position at the University of Auckland.

She has been a visiting scientist at Los Alamos National Laboratory (2003, 2005, 2006) and a visiting professor at the University of California at Davis (1993), the University of Heidelberg (2003) and the University of Burgundy (2004, 2006). She has been awarded a Fulbright Senior Scholar Award for 2007.

Her current research brings together her interests in porphyrin chemistry, the main group elements and organometallic chemistry. She investigates how the porphyrin ligand can be used to modify the chemistry of elements such as boron and bismuth, and as a ligand in complexes containing unusual chemical bonds between transition metal and main group elements. She has a number of research collaborations in NZ and internationally.

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Novel silicon-mediated transannular cyclopropanation

23 Jan 2013

An intriguing new method of transannular cyclopropanation has been reported by Prof. James Dowden‘s group at the University of Nottingham. This cyclopropanation, mediated by the presence of a trimethylsilyl group, allows the rapid formation of 4-azabicyclo(5.1.0)octenones (3) from simple starting materials. Divinyl beta-lactam (1) was elegantly formed via a Staudinger cycloaddition reaction beginning from 3-trimethylsilylpropenal, 4-methoxyaniline and crotonyl chloride. Next, researchers were able to transform 1 into dihydroazocinone (2) using a thermal Cope rearrangement.

The Dowden group discovered that if 2 was treated with TBAF or aqueous sodium hydroxide, 4-azabicyclo(5.1.0)octenone (3) could be formed. Interestingly, the reaction was dependent on the presence of the silicon group; when the trimethylsilyl group was replaced with an ester, no cyclopropanation occurred. The researchers proposed that the transannular cyclopropanation could be viewed as a Lewis-base–promoted Hosomi–Sakurai reaction proceeding via intramolecular 1,4-conjugate addition. 4-azabicyclo(5.1.0)octenones (3) are an unusual structural motif and it is hoped that this facile method for their construction may facilitate further examination of chemical space interactions.

Read this ‘HOT’ Chem Comm article today:

An unusual silicon mediated transannular cyclopropanation

Bing You, Kate Hamer, William Lewis and James Dowden

Chem. Commun., 2013, 49, 795-797

DOI: 10.1039/C2CC37739J

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Liquid crystal relaxation controlled by dopant kinetics

20 Jan 2013

Liquid crystals are an area of intense interest due to their potential use in smart materials such as displays. Cholesteric liquid crystals are of particular interest due to their helical nature and their ability to selectively reflect light over a narrow range of wavelengths. This range can be modified by the inclusion of photo-responsive dopants.

Dopants include overcrowded alkenes which undergo a stable to unstable (cis–trans) transition upon irradiation with UV light. This results in an unwinding and eventual inversion of the cholesteric helix. This is accompanied by a red-shift of the reflection band which then returns close to the original position. However, the handedness of the helix has changed, and therefore the polarization of the light has also changed.

Helix inversion of a cholesteric liquid crystal.

An important parameter with all liquid crystals is their relaxation step which needs to be suitable for the envisioned application. Nathalie Katsonis and her team have studied cholesteric liquid crystals doped with overcrowded alkenes in an effort to find a general paradigm correlating relaxation kinetics with the rate of helix inversion.

In their recent Communication, Katsonis’ group shows that the helix relaxation kinetics are fully determined by the kinetics of the light-sensitive dopants. The relaxation of the dopants from unstable to stable is unperturbed by the liquid crystalline environment.

On the other hand, the presence of the dopants can dramatically accelerate helix inversion. Therefore the inversion can be time-programmed by judicious choice of the dopant. This opens up the great potential of fine tuning cholesteric liquid crystals for smart materials with sophisticated functions.

For more, read this ‘HOT’ Chem Comm article in full:

Time-programmed helix inversion in phototunable liquid crystals

Sarah J. Aßhoff, Supitchaya Iamsaard, Alessandro Bosco, Jeroen J. L. M. Cornelissen, Ben L. Feringa and Nathalie Katsonis

Chem. Commun., 2013, Advance Article

DOI: 10.1039/C2CC37161H

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True racemic crystals: Surprising new insights on preparation and structure

16 Jan 2013

Isopropyl 3,3,3-trifluoro-2-hydroxypropanoate (1) is an important compound for the study of self-disproportionation of enantiomers (SDE), in which an enantiomerically enriched mixture can be separated into enantiopure and racemic portions under achiral conditions. This remarkable separation is made possible by the differences in physicochemical properties of enantiopure and racemic substances. Research led by Professor Vadim A. Soloshonok at the University of the Basque Country has now shed light on the unusual properties of racemic crystals of 1.

True racemic crystals were obtained by sublimation of a mixture of (S)- and (R)- crystal conglomerates at ambient temperature and atmospheric pressure. Surprisingly, when these racemic crystals were analysed, the unit cell was not dimeric in nature as previously thought, but rather contained two distinct (S)- and (R)- enantiomers with no heterochiral H-bonding. The preference of 1 for homochiral intermolecular interactions may explain its extraordinary ability for SDE. Indeed, Soloshonok and co-workers showed that achiral chromatography could be used to obtain enantiopure 1 from an original sample with just 75% ee (see above).

For more, read this ‘HOT’ Chem Comm article today:

Unconventional preparation of racemic crystals of isopropyl 3,3,3-trifluoro-2-hydroxypropanoate and their unusual crystallographic structure: the ultimate preference for homochiral intermolecular interactions

José Luis Aceña, Alexander E. Sorochinsky, Toshimasa Katagiri and Vadim A. Soloshonok

Chem. Commun., 2013, 49, 373–375

DOI: 10.1039/c2cc37491a

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A new way to look at cancer cell detection

14 Jan 2013

A novel cancer cell detection method, based on the interaction between daunomycin (DAN – an anticancer drug used in chemotherapy) and cell membrane components, has been developed by scientists in South Korea.

The method uses the electrochemical and fluorescence behaviour of DAN and uses an aptamer probe immobilised on a conducting polymer-gold nanoparticle composite film.

he aptamer sensor probes using electrochemical impedance spectroscopy and fluorescence microscopy. The method differentiates between cancerous and non-cancerous cells at low concentrations (0.01μM).

Read the ‘HOT’ Communication in full:

Cancer cell detection based on the interaction between an anticancer drug and cell membrane components
Pranjal Chandra , Hui-Bog Noh and Yoon-Bo Shim
Chem. Commun., 2013, DOI: 10.1039/C2CC38235K

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