Chemical Science Blog

Scientists in China have designed a velcro-like material held together by non-covalent interactions that can be unfastened by electrical means and refastened again under pressure.

The velcro is ‘stuck’ together by compressing a flexible, conductive poly(ionic liquid) membrane (PIL) functionalised with ferrocene (Fc) with a PIL functionalised with β-cyclodextrin (β-CD). The strong binding of the Fc groups within the β-CD cavities causes the layers to adhere together tightly. Oxidation of the Fc moieties to ferrocenium ions (Fc⁺) by chemical or electrochemical means causes the layers to come unstuck, as the charged Fc⁺ is not bound inside the hydrophobic β-CD cavity. A reducing potential and further pressing reassembles the material.

A hook-and-loop strategy fastens the layers together but these links can be unfastened by an electric current

Read the full article in Chemistry World»

Read the original journal article in Chemical Science – it’s free to download until 19th June:
Flexible and Voltage-Switchable Polymer Velcro Constructed by Host−Guest Recognition Between Poly(ionic liquid) Strips
Jiangna Guo, Chao Yuan, Mingyu Guo, Lei Wang and Feng Yan  
Chem. Sci., 2014, Accepted Manuscript
DOI: 10.1039/C4SC00864B, Edge Article

All of the referee-recommended articles below are free to access until 2nd June 2014

Functionalised staple linkages for modulating the cellular activity of stapled peptides
Yu Heng Lau, Peterson de Andrade, Soo-Tng Quah, Maxim Rossmann, Luca Laraia, Niklas Sköld, Tze Jing Sum, Pamela J. E. Rowling, Thomas L. Joseph, Chandra Verma, Marko Hyvönen, Laura S. Itzhaki, Ashok R. Venkitaraman, Christopher J. Brown, David P. Lane and David R. Spring  
Chem. Sci., 2014, 5, 1804-1809
DOI: 10.1039/C4SC00045E, Edge Article

Single molecule analysis of light-regulated RNA:spiropyran interactions
Xing Zhang, Junji Zhang, Yi-Lun Ying, He Tian and Yi-Tao Long  
Chem. Sci., 2014, Advance Article
DOI: 10.1039/C4SC00134F, Edge Article

Imine-Based Chiroptical Sensing for Analysis of Chiral Amines: From Method Design to Synthetic Application
Leo A Joyce, Edward Sherer and Christopher J Welch  
Chem. Sci., 2014, Accepted Manuscript
DOI: 10.1039/C4SC01006J, Edge Article

Decoding the infrared signatures of pyramidal carbons in graphenic molecular nanostructures of interstellar origin
Héctor Álvaro Galué  
Chem. Sci., 2014, Advance Article
DOI: 10.1039/C4SC00890A, Edge Article

Chinese chemists have created an epoxy that can be rapidly hardened and reshaped by shining a light on it. Unlike traditional epoxies which are cured using heat, this approach uses carbon nanotubes to translate light energy into localised heat to set the epoxy. Shining additional light on the set polymer initiates self-healing and reshaping.

Read the full article in Chemistry World»

Read the original journal article in Chemical Science – it’s free to access until 17th June:
Carbon nanotube-Vitrimer composite for facile and efficient photo-welding of epoxy
Yang Yang, Zhiqiang Pei, Xiqi Zhang, lei tao, yen wei and Yan Ji  
Chem. Sci., 2014, Accepted Manuscript, DOI: 10.1039/C4SC00543K, Edge Article

For over 20 years the infrared spectra of many astronomical objects have been interpreted as flat two-dimensional polycyclic aromatic hydrocarbons (PAHs) that are also thought to be the source of organic matter on our own planet. More recently the detection of molecules such as fullerenes – molecules composed entirely of carbon, including the spherical C₆₀ – has revealed a more complicated picture of carbon in space. The links between these different molecules have been rather unclear but new research from Héctor Alvaro Galué at VU University of Amsterdam, in the Netherlands, has taken a fresh approach to this long-standing puzzle.

Energetic particles in interstellar space induce strain and re-hybridisation within flat carbon structures. Background image: © NASA, ESA, M Robberto (Space Telescope Science Institute/ESA) and the Hubble Space Telescope Orion Treasury Project Team

Read the full article in Chemistry World»

Read the original journal article in Chemical Science – it’s free to download until 6th June:
Decoding the infrared signatures of pyramidal carbons in graphenic molecular nanostructures of interstellar origin
Hector Alvaro Galue  
Chem. Sci., 2014, Accepted Manuscript, DOI: 10.1039/C4SC00890A, Edge Article

Scientists in Canada have made DNA cubes that are programmed to unzip and reveal molecules locked inside them in response to a carefully chosen trigger. Hanadi Sleiman and colleagues at McGill University and the Jewish General Hospital in Montreal, designed the cubes to release the drug cargo they might be carrying only in diseased cells and not normal cells.

The mRNA trigger binds tothe overhangs and opens the cube by strand displacement and strategically placed nicks on the structure

Read the full article in Chemistry World»

Read the original journal article in Chemical Science – it’s free to download until 7th May:
Sequence-responsive unzipping DNA cubes with tunable cellular uptake profiles
Katherine E. Bujold, Johans Fakhoury, Thomas G. W. Edwardson, Karina M. M. Carneiro, Joel Neves Briard, Antoine G. Godin, Lilian Amrein, Graham D. Hamblin, Lawrence C. Panasci, Paul W. Wiseman and Hanadi F. Sleiman  
Chem. Sci., 2014, Advance Article, DOI: 10.1039/C4SC00646A, Edge Article

All of the articles below are free to access until 14th May

Boron–boron J coupling constants are unique probes of electronic structure: a solid-state NMR and molecular orbital study
Frédéric A. Perras and David L. Bryce  
Chem. Sci., 2014, Advance Article
DOI: 10.1039/C4SC00603H, Edge Article

Disubstituted sialic acid ligands targeting siglecs CD33 and CD22 associated with myeloid leukaemias and B cell lymphomas
Cory D. Rillahan, Matthew S. Macauley, Erik Schwartz, Yuan He, Ryan McBride, Britni M. Arlian, Janani Rangarajan, Valery V. Fokin and James C. Paulson  
Chem. Sci., 2014, Advance Article
DOI: 10.1039/C4SC00451E, Edge Article

Solvatochromic AIE luminogens as supersensitive water detectors in organic solvents and highly efficient cyanide chemosensors in water
Yuping Zhang, Dongdong Li, Yi Li and Jihong Yu  
Chem. Sci., 2014, Accepted Manuscript
DOI: 10.1039/C4SC00721B, Edge Article

Catalytic enantioselective synthesis of 2-aryl-chromenes
Bi-Shun Zeng, Xinyi Yu, Paul W. Siu and Karl A. Scheidt  
Chem. Sci., 2014, Advance Article
DOI: 10.1039/C4SC00423J, Edge Article

All of the articles below are free to access until 13th April 

Turn-ON fluorescent affinity labeling using a small bifunctional O-nitrobenzoxadiazole unit
Takao Yamaguchi, Miwako Asanuma, Shuichi Nakanishi, Yohei Saito, Masateru Okazaki, Kosuke Dodo and Mikiko Sodeoka
Chem. Sci., 2014,5, 1021-1029
DOI: 10.1039/C3SC52704B, Edge Article  

DNAzyme-based 2:1 and 4:1 multiplexers and 1:2 demultiplexer
Ron Orbach, Francoise Remacle, R. D. Levine and Itamar Willner
Chem. Sci., 2014,5, 1074-1081
DOI: 10.1039/C3SC52752B, Edge Article  

Incorporation of electrically charged N-alkyl amino acids into ribosomally synthesized peptides via post-translational conversion
Takashi Kawakami, Toru Sasaki, Patrick C. Reid and Hiroshi Murakami
Chem. Sci., 2014,5, 887-893
DOI: 10.1039/C3SC52744A, Edge Article   

   Click here for more free hot Chemical Science articles for March

Montelukast works by blocking the action of chemicals released by the body as part of allergic and inflammatory reactions

Scientists based in the US have devised a new way to make Montelukast, a drug used in the treatment of asthma and seasonal allergies.

Asthma is a chronic inflammatory disease of the airways which affects up to 300 million people worldwide and caused 250,000 deaths in 2011. Although there is no cure for asthma, symptoms can be managed through the use of fast-acting medication to treat acute attacks, and long-term control achieved using inhaled corticosteroids, sometimes in conjunction with a leukotriene antagonist, such as Montelukast.

Read the full article in Chemistry World»

Read the original journal article in Chemical Science – it’s free to access until 28th April:
Iron catalyzed enantioselective sulfa-Michael addition: a four-step synthesis of the anti-asthma agent Montelukast
James D. White and Subrata Shaw  
Chem. Sci., 2014, DOI: 10.1039/C4SC00051J