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Nanoparticles help reveal hidden fingerprints

04 Apr 2011

Criminal investigations may benefit from new forensic methods based on nanoparticles. A technique using gold nanoparticles in combination with antibodies has shown promising results for enhancing fingerprints that are over a week old.

Fingerprinting, first reported in the 19th century, is still the primary source of evidence used in crime scene investigation and new methods for improving fingerprint visualisation remain in demand. Unseen (latent) fingerprints can be revealed using chemical treatments that target molecules likely to be deposited in fingerprints, such as those in hair follicle secretions.

Xanthe Spindler at the University of Technology Sydney in Australia and colleagues now report a technique that targets amino acids – present ubiquitously in sweat and thus in most fingerprints. They linked amino acid-binding antibodies to gold nanoparticles and applied them to fingerprints. To develop and image the prints, they used red fluorescent secondary antibodies that would stick to the nanoparticle-bound antibodies.

: Antibodies bound to nanoparticles can bind to amino acids in fingerprints that are over 12 months old

Read the full news story in Chemistry World and Spindler’s ChemComm communication to find out more.

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A supramolecular approach to zwitterionic metal silanides

31 Mar 2011

Zwitterionic metal silanides represent a structurally novel class of tri-coordinated silyl anions in which the cationic metal centre is separated from the silicon anion by internal donor bridges.

Clemens Krempner and co-workers have now reported that key to the synthesis of stable, isolable species is the use of pendant polydonor groups that exclusively bind to the metal cation and serve to prevent self-aggregation.

Due to the shape of these unusual compounds, the electron pair located at the central silicon anion is available for additional metal binding. This has allowed for the synthesis of hitherto unknown zwitterionic heterobimetallic silanides, by reaction of the zwitterionic metal silanides with boron, aluminium or tungsten-containing species.

To read about these intriguing compounds in more detail, download the ChemComm communication, which is available for free until April 28th.

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Catalytic reaction cascade forms substituted pyrroles

31 Mar 2011

Catalytic reaction cascades present a neat, efficient way to synthesise valuable organic molecules. However, their success relies upon the compatibilty of the reactants and catalysts involved, and identifying this requires ingenuity and experimentation.

Now Darren Dixon and co-workers at the University of Oxford have reported a one-pot nitro-Mannich/hydroamination cascade for direct synthesis of 2,5-disubstituted pyrroles from imines and nitro alkynes. The reaction is catalysed by base and a gold(I) catalyst, and has been optimised to achieve yields up to 86%.

To find out more download the ChemComm communication, which is free to access until April 28th

Start a discussion by leaving your comments below

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A Sustainable Global Society: How Can Materials Chemistry Help?

31 Mar 2011

A high profile white paper A Sustainable Global Society: How Can Materials Chemistry Help? was launched internationally on 27 March.

The output of the Chemical Sciences and Society Summit (CS3) 2010, which took place in London, September 2010, outlines five key areas in which materials chemists, through collaboration with other scientists, industry and policy makers, can seize exciting opportunities to address global challenges. This project was driven by the RSC and is a collaboration between the chemical societies of China, Germany, Japan, the US, the UK and national funding bodies. Around 30 leading materials chemists from the participating nations participated in CS3 2010 and the white paper is a reflection of the outcome of the summit, in particular their view of the future direction for materials chemistry.

View the official website of the white paper.

Read the 27 March press release.

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New tool for speeding up porous materials discovery

28 Mar 2011

A new tool (Infrasorb-12) for screening porosity has been developed by scientists in Germany. The tool identifies high surface area materials in a very short time with high accuracy. The researchers say that Infrasorb-12 development will speed up the discovery of new porous materials significantly and broaden the wide range of materials suitable for gas storage, selective adsorption, catalysis, and life science applications.

Further information:
High-throughput screening: speeding up porous materials discovery
Philipp Wollmann, Matthias Leistner, Ulrich Stoeck, Ronny Grünker, Kristina Gedrich, Nicole Klein, Oliver Throl, Wulf Grählert, Irena Senkovska, Frieder Dreisbach and Stefan Kaskel, Chem. Commun., 2011, DOI: 10.1039/C1CC10674K

Also of interest:
Modifying MOFs: new chemistry, new materials
Seth M. Cohen, Chem. Sci., 2010, 1, 32-36 (DOI: 10.1039/C0SC00127A)

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Carbon dioxide adsorption in porous phosphine coordination material

28 Mar 2011

US, UK and Korean scientists have made a new porous phosphine coordination material, PCM-11. The material is an unusual 8,4-connected coordination polymer with an open 3-D pore structure, say the researchers.

The team formed the material by reacting Mg(II) with tris(para-carboxylato)triphenylphosphine oxide. The highly ionic nature of the metal–ligand bonding results in excellent thermal stability upon desolvation (>460 ºC), they say. PCM-11 is easily activated for small molecule sorption at low temperature without the requirement for solvent pre-exchange. It adsorbs 47.5 wt% CO₂ at 11.6 bar and 30ºC.

Find out more in the ChemComm communication:
High capacity CO₂ adsorption in a Mg(II)-based phosphine oxide coordination material
Alisha M. Bohnsack, Ilich A. Ibarra, Peter W. Hatfield, Ji Woong Yoon, Young Kyu Hwang, Jong-San Chang and Simon M. Humphrey, Chem. Commun., 2011, DOI: 10.1039/C1CC10754B

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Novel methodologies for synthesising pyroglutamates

04 Mar 2011

Several pyroglutamate-based natural products have been found to exhibit potent anti-cancer and anti-microbial properties. Although their syntheses have been a focus of research for many groups, their is still room for improvement in the development of highly tunable methodologies for the diverse functionalisation of the pyroglutamate ring.

Venkatram R. Mereddy and co-workers have developed a novel and exceptionally short methodology for the synthesis of such functionalised pyroglutamates via alkylation of amino acid-derived iminoesters with allyl bromides or allyl acetates, easily obtained by Bayliss-Hilman reaction.

To learn more download the ChemComm communication, available for free until March 28th

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A new class of molecular propellers

28 Feb 2011

Scientist based in Italy have recently demonstrated a new class of molecular propellers based upon polyoxometalates (POMs).

POMs consist of a cluster of transition metal oxides that are water soluble and are used for a wide range of applications. In particular, Andrea Sartorel and Marcella Bonchio, from the Univerity of Padova, are interested in their use as photosynthetic oxygen-evolving catalysts. The team studied a series of POMs with different metal centres and their catalytic performance in the disproportionation of hydrogen peroxide (H₂O₂) to water and oxygen.

They found that of all the POMS studied, Ru₄(SiW₁₀)₂ performed the best in terms of oxygen evolution. This production of oxygen could then be used to create movement of the POM; in effect using H₂O₂as fuel to create oxygen that then propels the POM material in aqueous solution. A video of this can be seen here. This represents a step towards the use of light-driven molecular machines based on POMs.

If you are interested in finding out more, then why not download Sartorel and Bonchio’s ChemComm article for free today? Also, don’t forget to leave a comment below!

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Intramolecular cycloaddition leads to the pentacyclic core of cortistatins

28 Feb 2011

Synthesising intriguing bioactive natural products in the most expedient and atom-efficient manner remains a highly active and competitive field of research. Cortistatins A and J, first isolated from the marine sponge Corticium simplex in 2006, have been identified as effective anti-angiogenics, which studies have found could suppress cancer recurrence when given in conjunction with traditional cancer drugs.

Lok Lok Liu and Pauline Chiu at the University of Hong Kong have reported a concise, high yielding, asymmetric synthesis of the pentacyclic framework of the cortistatins, in 12 steps from commercially available starting materials. Their synthesis employs a highly diastereoselective intramolecular [4+3] cycloaddition of epoxy enolsilanes as the key step and brings them close to their ultimate goal.

To find out more, download the ChemComm communication for free up until March 28th

To start a discussion, leave your comments below and for a related blog post see the Totally Synthetic blog pages.

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Meet our author… Greg Qiao

23 Feb 2011

Greg Qiao is a polymer scientist and engineer at the University of Melbourne in Australia. His research interests cover various polymerisation techniques, including controlled free radical polymerisations, in a bid to synthesise novel polymeric architectures, biodegradable and functional polymers.

Qiao’s recent communication, published in ChemComm, touches upon his interest in using polymers as coatings for the automotive industry or as potential drug delivery vehicles: ‘Star Polymers Composed Entirely of Amino Acid Building Blocks: A Route towards Stereospecific, Biodegradable and Hierarchically Functionalized Stars‘

Below, Greg takes some time away from his research to talk to us…

What initially inspired you to become a scientist?
When I was a child, I always dreamed of becoming a scientist. I chose science and engineering as my major when starting university and fell in love with both chemistry and chemical engineering. I’ve always believed that science and technology can change and improve life for the human society.

Greg Qiao

What was your motivation behind the work described in your ChemComm article?
My research group has spent over 10 years in the field of controlled synthesis and characterisation of core crosslinked star (CCS) polymers. We initially used controlled free radical polymerisation methods, including nitroxide–mediated polymerisation (NMP) and atom transfer radical polymerisation (ATRP) methods, to synthesise CCS polymers and study their properties including molecular morphology and solution rheology. We also studied CCS analogues for their suitability as additive to automotive paint.
Five years ago, we started to synthesise CCS polymers with alternative polymerisation methods including ring opening polymerisation (ROP) for selectively degradable CCS. More recently, we have been working on new ways to form CCS which is fully biodegradable and biocompatible. In this work, we developed a new process by using peptide synthesis as a controlled chain growth method to produce CCS. This process not only uses entirely naturally occurred amino-acid precursors, but also provides more convenient approaches to functionalise CCS at its core, along the arms and at the end of the arms. We are hoping this work can lay foundation for the new peptide-based drug delivery vehicles.

Why did you choose ChemComm to publish your work?
Because of the fast and broad readership, as well as its high impact.

Where do you see your research heading next?
We wish to develop this unique peptide-based CCS as a drug carrier for delivering drugs to targeted cells. My other research direction is using the controlled polymerisation method to create an efficient and thickness-controlled surface coating technology.

What do enjoy doing in your spare time?
Reading a good article that has a completely fresh, new idea.

If you could not be a scientist, but could be anything else, what would you be?
Politician or publican servant – something to serve the public.

Other polymer articles recently published in ChemComm that might also interest you include:-

Emerging synthetic approaches for protein–polymer conjugations
Rebecca M. Broyer, Gregory N. Grover and Heather D. Maynard
Chem. Commun., 2011, 47, 2212-2226
DOI: 10.1039/C0CC04062B, Feature Article

Functional, star polymeric molecular carriers, built from biodegradable microgel/nanogel cores
Jay A. Syrett, David M. Haddleton, Michael R. Whittaker, Thomas P. Davis and Cyrille Boyer
Chem. Commun., 2011, 47, 1449-1451
DOI: 10.1039/C0CC04532B, Communication

A synthetic approach to a fullerene-rich dendron and its linear polymer via ring-opening metathesis polymerization
Jonggi Kim, Myoung Hee Yun, Junghoon Lee, Jin Young Kim, Fred Wudl and Changduk Yang
Chem. Commun., 2011, Advance Article
DOI: 10.1039/C0CC05470D, Communication

Cationic and charge-neutral calcium tetrahydroborate complexes and their use in the controlled ring-opening polymerisation of rac-lactide
Michael G. Cushion and Philip Mountford
Chem. Commun., 2011, 47, 2276-2278
DOI: 10.1039/C0CC04348F, Communication

And also from our sister journal Chemical Science, a Perspective and an Edge Article for you to read:-

Triggered structural and property changes in polymeric nanomaterials
Jason M. Spruell and Craig J. Hawker
Chem. Sci., 2011, 2, 18-26

Cylindrical micelles from the living crystallization-driven self-assembly of poly(lactide)-containing block copolymers
Nikos Petzetakis, Andrew P. Dove and Rachel K. O’Reilly
Chem. Sci., 2011, Advance Article

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Chemical Communications Blog

Archive for the ‘Subject Areas’ Category

Nanoparticles help reveal hidden fingerprints

A supramolecular approach to zwitterionic metal silanides

Catalytic reaction cascade forms substituted pyrroles

A Sustainable Global Society: How Can Materials Chemistry Help?

New tool for speeding up porous materials discovery

Carbon dioxide adsorption in porous phosphine coordination material

Novel methodologies for synthesising pyroglutamates

A new class of molecular propellers

Intramolecular cycloaddition leads to the pentacyclic core of cortistatins

Meet our author… Greg Qiao

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