Archive for the ‘Hot articles’ Category

Hot papers in RSC Advances: Medicinal

Enjoy reading the latest Hot articles in RSC Advances from the Medicinal category – free to access until the 7th August 2013!

De novo design of immunoreactive conformation-specific HIV-1 epitopes based on Top7 scaffold
Isabelle F. T. Viana, Thereza A. Soares, Lucianna F. O. Lima, Ernesto T. A. Marques, Marco A. Krieger, Rafael Dhalia and Roberto D. Lins
RSC Adv., 2013, 3, 11790-11800, DOI: 10.1039/C3RA41562G

Graphical abstract for C3RA41562G

Radio-opaque theranostic nanoemulsions with synergistic anti-cancer activity of paclitaxel and Bcl-2 siRNA
Mi Hwa Oh, Jee Seon Kim, Jeong Yu Lee, Tae Gwan Park and Yoon Sung Nam
RSC Adv., 2013, Advance Article, DOI: 10.1039/C3RA40883C

Graphical abstract for C3RA40883C

Pore size-optimized periodic mesoporous organosilicas for the enrichment of peptides and polymers
Kun Qian, Fang Liu, Jie Yang, Xiaodan Huang, Wenyi Gu, Siddharth Jambhrunkar, Pei Yuan and Chengzhong Yu
RSC Adv., 2013, Advance Article, DOI: 10.1039/C3RA41332B

Graphical abstract for C3RA41332B

Nucleobase-grafted polycaprolactones as reversible networks in a novel biocompatible material
I.-Hong Lin, Chih-Chia Cheng, Cheng-Wei Huang, Mei-Chih Liang, Jem-Kun Chen, Fu-Hsiang Ko, Chih-Wei Chu, Chih-Feng Huang and Feng-Chih Chang
RSC Adv., 2013, Advance Article, DOI: 10.1039/C3RA41412D

Graphical abstract for C3RA41412D

Molecular docking, design, synthesis and antifungal activity study of novel triazole derivatives containing the 1,2,3-triazole group
Shichong Yu, Lunuan Wang, Yanwei Wang, Yang Song, Yongbing Cao, Yuanying Jiang, Qingyan Sun and Qiuye Wu
RSC Adv., 2013, Advance Article, DOI: 10.1039/C3RA41310A

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

HOT papers in RSC Advances

Here are the latest HOT papers published in RSC Advances, as recommended by the referees:

Synthesis of amine-tagged metal–organic frameworks isostructural to MIL-101(Cr)
Ricardo B. Ferreira, Perry M. Scheetz and André L. B. Formiga  
RSC Adv., 2013, 3, 10181-10184, DOI: 10.1039/C3RA23443F

C3RA23443F graohical abstract

The gradient distribution of Ni ions in cation-disordered Li[Ni1/2Mn3/2]O4 clarified by muon-spin rotation and relaxation (μSR)
Kazuhiko Mukai, Yutaka Ikedo, Kazuya Kamazawa, Jess H. Brewer, Eduardo J. Ansaldo, Kim H. Chow, Martin Månsson and Jun Sugiyama
RSC Adv., 2013, Advance Article, DOI: 10.1039/C3RA40878G

 Graphical abstract for C3RA40878G

Molecular templates and nano-reactors: two-dimensional hydrogen bonded supramolecular networks on solid/liquid interfaces
Xuemei Zhang, Qingdao Zeng and Chen Wang  
RSC Adv., 2013, Advance Article, DOI: 10.1039/C3RA40473K

C3RA40473K graphical abstract
 

All the papers listed above are free to access for the next 4 weeks!

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Better batteries to support wind and solar

I seem to be talking rather a lot about energy just lately, but there is no denying it is a subject that comes up time and again.

Non-aqueous redox flow batteries (RFBs) are a technology aimed at supporting intermittent renewable energy sources such as wind and solar, by storing the energy they produce and releasing it on demand. The challenges in developing better batteries of this type are related to optimising their cell potential and designing new membrane materials to minimise cross-mixing and improve selectivity.

This review by researchers at GIST in the Republic of Korea concentrates on reported methods of preparation and characterisation of the anion exchange membranes, and also covers the general principles of RFBs which are necessary to understand the issues involved in membrane development.Non aqueous redox flow battery schematic

They start from the premise that non-aqueous RFBs are better than aqueous RFBs due to the higher energy densities made possible by the wider cell potential range that is available in solvents other than water. Metal-ligand complexes have been the main focus of research as the redox couple.

Redox couples studied in detail have included ruthenium, vanadium, chromium, manganese, nickel, iron, cobalt and uranium based systems. Those based on ruthenium, for example, have improved efficiency since the oppositely charged species generated during charging tend to revert to the same reactive species during discharge, reducing cross-over.

Electrode materials that have been investigated include glassy carbon, platinum or gold.

Read the full review in RSC Advancesfree to access for 4 weeks:

A review of current developments in non-aqueous redox flow batteries: characterization of their membranes for design perspective, Sung-Hee Shin, Sung-Hyun Yun and Seung-Hyeon Moon, RSC Adv., 2013, 3, 9095.

Stay up-to-date with the latest content in RSC Advances by registering for our free newsletter and table of contents alerts.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

HOT papers in RSC Advances

Here are the latest HOT papers published in RSC Advances, as recommended by the referees:

Acidity and basicity of halometallate-based ionic liquids from X-ray photoelectron spectroscopy
Alasdair W. Taylor, Shuang Men, Coby J. Clarke and Peter Licence  
RSC Adv., 2013, Advance Article, DOI: 10.1039/C3RA40260F

graphical abstract for c3ra40260f

 

Parameters in preparation and characterization of cross linked enzyme aggregates (CLEAs)
Sachin Talekar, Asavari Joshi, Gandhali Joshi, Priyanka Kamat, Rutumbara Haripurkar and Shashikant Kambale  
RSC Adv., 2013, Advance Article, DOI: 10.1039/C3RA40818C

graphical abstract for c3ra40818c

 

Stereoselective approach to aminocyclopentitols from Garner aldehydes
Sanjit Kumar Das and Gautam Panda  
RSC Adv., 2013, Advance Article, DOI: 10.1039/C3RA40648B, Paper

graphical abstract for c3ra40648b

 

All the papers listed above are free to access for the next 4 weeks!

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Graphene and platinum are brought together for fuel cells

Graphene is certainly a hot topic in research right now. A quick look down this very blog shows that it featured in no fewer than seven of the top ten accessed articles in RSC Advances during 2012 (including all of the top three)!

This versatile material appears as oxides, composites, quantum dots, nanomaterials and foams and it has been investigated for uses in photocatalysis, energy, environmental applications and more.

Now researchers in India and China have been investigating graphene supported platinum catalysts for fuel cells.Platinum nanostructures on graphene catalysing oxygen reduction

Sreekuttan M. Unni and colleagues report the first synthesis of a 3D self-assembled single crystalline platinum nanostructure directly on a graphene surface without structural directing agents, by using a slow reduction method. In their paper, they show superior electrocatalytic activity towards the oxygen reduction reaction, a crucial reaction for hydrogen-fuelled polymer electrolyte fuel cells. They show that their material also has less vulnerability to strong hydroxyl adsorption and a higher limiting current density than other graphene supported platinum or commercial platinum-on-carbon catalysts.

Meanwhile Jian Zhao and colleagues have published about their supercritical fluid route for preparing graphene-supported platinum-ruthenium nanoparticles in an effective, simple, low temperature and environmentally benign way. They used supercritical CO2 to uniformly distribute ultrafine PtRu nanoparticles with an average size of 2.87 nm on the surfaces of functionalized graphene sheets. They found considerably improved catalytic activity and stability for methanol oxidation from their supported nanoparticles because of the uniform distribution. Their supercritical approach may have promise for development of direct methanol fuel cells.

Find out more about this research in RSC Advances:

3-Dimensionally self-assembled single crystalline platinum nanostructures on few-layer graphene as an efficient oxygen reduction electrocatalyst, Sreekuttan M. Unni, Vijayamohanan K. Pillai and Sreekumar Kurungot, RSC Adv., 2013, 3, 6913-6921

Methanol electrocatalytic oxidation on highly dispersed platinum–ruthenium/graphene catalysts prepared in supercritical carbon dioxide–methanol solution, Jian Zhao, Lin Zhang, Hao Xue, Zhaobo Wang and Haiqing Hu, RSC Adv., 2012, 2, 9651–9659

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Creative assemblies for targeted drug delivery

Stimuli-responsive assemblies have generated a lot of interest in recent years especially in view of their biological applications.  Enzyme-responsive assemblies for controlled drug release have gained particular interest as this offers potentially selective and targeted delivery of therapeutics.Graphical Abstract for C3RA40453F

A team of scientists from Nankai University (China) led by Yu Liu have fabricated a supramolecular assembly based on the host-guest complexation of amphiphillic calixarene with adenosine triphosphate (ATP).  Complextion of the calixarene with ATP markedly lowers it’s critical aggregation concentration, forming hollow spherical nanoparticles.  The nanospheres were shown to be responsive to phosphatase – an enzyme over-expressed in many tumor cells – and thus may have applications in drug delivery and cancer therapy.

Read the full article for free until the 24th May 2013:

Phosphatase-responsive amphiphilic calixarene assembly, Yi-Xuan Wang, Dong-Sheng Guo, Yu Caoa and Yu Liu, RSC Adv., 2013, DOI: 10.1039/C3RA40453F

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Energy storage of the future?

Supercapacitors, also known as electrochemical capacitors, are used as highly reliable energy storage devices with the advantage of rapid charge and discharge compared to batteries. However to further expand their use it is necessary to improve their performance in other areas including energy density.

Ruthenium oxide is the material widely used for supercapacitor electrodes. Its use is reviewed by Wentao Deng and colleagues in China and the UK, in a comprehensive overview of the state-of-the-art in this area.Ruthenium oxide decorated carbon nanotubes for supercapacitors

Work has not stopped on improving the performance of these highly promising devices – far from it. Just to take a couple of examples, Sho Makino and colleagues from Japan have used nanostructured ruthenium oxide in an aqueous hybrid supercapacitor with a specific energy comparable to modern rechargeable batteries, opening the possibility of using these materials in a post-lithium ion battery technology. Meanwhile Beena Balan and colleagues from India have looked at decorating carbon nanotubes with ruthenium oxide to produce a ternary electrode material to increase the specific capacitance by 103%, with enhanced rate and excellent electrochemical stability.

Read more about this valuable research in RSC Advances – free to access for 4 weeks:

Electrochemical capacitors utilising transition metal oxides: an update of recent developments, Wentao Deng, Xiaobo Ji, Qiyuan Chen and Craig E. Banks, RSC Adv., 2011, 1, 1171

4 V class aqueous hybrid electrochemical capacitor with battery-like capacity,Sho Makino, Yuto Shinohara, Takayuki Ban, Wataru Shimizu, Keita Takahashi, Nobuyuki Imanishib and Wataru Sugimoto, RSC Adv., 2012, 2, 12144

Carbon nanofiber–RuO2–poly(benzimidazole) ternary hybrids for improved supercapacitor performance, Beena K Balan, Harshal D Chaudhari, Ulhas K Kharul and Sreekumar Kurungot, RSC Adv., 2013, 3, 2428

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Electron-conjugation facilitates electron transfer of hemoglobin by Ce(OH)3 nanorods

Scientists from the University of Chinese Academy of Sciences (Beijing, China) led by Kebin Zhou investigated the interaction between nanorods of Ce(OH)3 and CeO2 and the redox protein hemoglobin.

Graphical abstract for C3RA40336JThe nano-bio interfaces, such as those between inorganic nanomaterials and biological systems, are gaining a significant amount of interest due to their importance in biomedical applications, but also out of concerns over the bio-safety of nano-engineered particles.  In the case of ceria-based nanomaterials, some studies have found they were able to prevent the increase of reactive oxygen species (ROS) in vitro and in vivo due to the existence of Ce3+.  However, others have found that some of these materials could actually generate ROS and cause toxicity to cells as Ce4+ is reduced to Ce3+.

In this work, Zhou and co-workers hydrothermally prepared Ce(OH)3 and CeO2 nanorods and studied their interaction with a typical redox protein hemoglobin through an electrochemical method combined with Electron Paramagnetic Resonance spectroscopy.  Ce(OH)3 was found to be more efficient in enhancing the direct electron-transfer of hemoglobin which may be due to the strong electron-conjugation interaction.

Read the full article for free until the 7th May 2013.

Strong electron-conjugation interaction facilitates electron transfer of hemoglobin by Ce(OH)3nanorods, Lei Wang, Qingfen Luan, Dan Yang, Xin Yao and Kebin Zhou, RSC Adv., 2013, DOI: 10.1039/C3RA40336J

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Flexible ligand secret to solvent-free success

Steven P. Nolan’s group at the University of St Andrews in Scotland, UK, have reported a new solvent-free protocol for carrying out Buchwald-Hartwig aminations, an important class of reactions, for unactivated aryl chlorides using a palladium pre-catalyst. The reaction proceeds to complete conversion in around five minutes when initiated at room temperature, compared to zero conversion when using a solvent (DME). The secret to their success appears to be the use of a bulky yet flexible ligand, IPr*, in the pre-catalyst.

A highly effective solvent-free protocol for the Buchwald–Hartwig amination of unactivated aryl chlorides by palladium pre catalyst

The reaction requires 1 mol% of the [Pd(NHC)] pre-catalyst – halving the amount of catalyst halved the conversion rate. An exotherm was observed in many cases: the reaction self-heated to 80ºC for a few seconds, therefore the group concludes that the protocol could be dangerous if carried out at a large scale. Interestingly the coupling could also be carried out with a solid substrate, leading to conversion of 73% after 24h, with no observed exotherm but a longer reaction time.

To learn more about this intriguing class of reactions, read the original article in RSC Advances:

Solvent-free aryl amination catalysed by [Pd(NHC)] Complexes, Anthony Chartoire, Arnaud Boreux, Anthony R. Martin and Steven P. Nolan, RSC Adv., 2013, 3, 3840–3843

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Bone-repairing nanoparticles laced with DNA

A bone-repairing nanoparticle paste has been developed that promises faster repair of fractures and breakages. DNA containing two growth-factor genes is encapsulated inside synthetic calcium-phosphate nanoparticles. These genes can enter cells and induce the synthesis of proteins that are able to accelerate bone growth.

The treatment of bone loss or fracture – after trauma, surgery or tumour extractions, for instance – represents a major challenge in clinical medicine. Matthias Epple at the University of Duisburg-Essen, Germany, who leads the team that developed the new bone paste, explains that ‘alternatives, such as bone from donors and synthetic calcium phosphate, suffer from infection problems, poor mechanical stability or inadequate resorption to form new bone.’ The team’s approach combines the bone-forming action of calcium phosphate – the principal component of bone – at the site of injection with further stimulation of bone growth in the surrounding tissue.

Injecting the paste into the boneGenes for two growth factors are encapsulated within the nanoparticles: bone morphogenetic protein 7 (BMP-7), which stimulates bone-forming cells, and vascular endothelial growth factor (VEGF), which induces the growth of blood vessels for bone-cell nutrition. Following injection, the nanoparticles are taken up by the surrounding cells, where the acidic conditions of the lysosomes dissolves the calcium phosphate and releases the DNA. These transfected cells then produce the growth factors that accelerate bone growth and reduce the amount of time a patient is immobile. Epple expects a long-lasting stimulatory effect that will aid growth over the months and years required for bones to heal fully, preventing the need for multiple injections.

Michael Hofmann, who works on bone cements and drug delivery at the University of Birmingham, UK, remarks: ‘The bioresorbable paste would be replaced quickly by newly formed bone, so effectively you would have a vanishing implant. In a population where an increasing number of people have impaired bone-growth abilities – for instance, the elderly – the findings have tremendous potential for accelerating the regrowth of any bone loss or fracture in orthopaedic and dental applications.’

Epple’s team plan to extend their work on calcium-phosphate nanoparticles to target specific cell types by attaching antibodies to the nanoparticle surface.

by Michael Parkin

The above story was published in Chemistry World on the 13th February 2013: Bone-repairing nanoparticles laced with DNA

Read the full article for free until the 29th March 2013! 

A genetically active nano-calcium phosphate paste for bone substitution, encoding the formation of BMP-7 and VEGF-A, Svetlana Chernousova, Jan Klesing, Nadia Soklakova and Matthias Epple, RSC Adv., 2013, DOI: 10.1039/C3RA23450A

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)