Archive for the ‘Chemistry World Articles’ Category

Micromotors navigate tiny biochemical lab

Micromotors have been used for a wide range of applications, from hydrogen generation and bacteria capture, and now scientists from the University of Alcalá, Spain have utilised these useful micromachines in a lab-on-a-chip device. The little machines can navigate through the confined space to carry out fluorescence-based detection and even transport cargo in a complex medium that simulates blood plasma. There is no need for complex valves or pumps, just a simple magnetic field.

Described by nanobioelectronics and nanomotor experts as “a wonderful example” of carbon-based rockets for active transport showcasing a “potential breakthrough” as one of “very few practical applications”. Of particular importance is the incorporation of an anti-fouling layer that allows the micromotors to travel through complex mediums without degrading. This has the potential to overcome on of the key limiting factors in the advancement of biomedical applications in this field.

Read the full article in Chemistry World.

 

R. Maria-Hormigos, B. Jurado-Sánchez and A. Escarpa
Nanoscale, 2017,9, 6286-6290
DOI: 10.1039/C6NR09750B, Communicaton
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)

Siligraphene gets serious about solar cells: Nanoscale article featured in Chemistry World

Theoretical scientists have predicted SiC7 – a new phase of the graphene–silicene hybrid siligraphene, which if synthesisable, could revolutionise flexible optoelectronic devices such as solar cells.

A charge density map reveals delocalised π bonds in SiC7 siligraphene's irregular hexagonal rings

SiC7 siligraphene has an interesting structure with a graphene-like honeycomb lattice, but unlike graphene, its hexagonal rings are irregular. The scientists expect SiC7 siligraphene to be much better than SiC2 siligraphene and single-layer black phosphorus at absorbing sunlight. Additionally, broken symmetry caused by silicon doping would create band gaps that boost its optoelectronic properties.

Interested to know more? Read the full article by Suzanne Howson in Chemistry World.

The original article is free to access and can be read at:

SiC7 siligraphene: a novel donor material with extraordinary sunlight absorption
Huilong Dong, Liujiang Zhou, Thomas Frauenheim, Tingjun Hou, Shuit-Tong Lee and Youyong Li
Nanoscale, 2016,8, 6994-6999.

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)

3D nanoprinting pen

A pen that performs 3D printing on the nanoscale has been developed by scientists in South Korea.

The pen, created by Seongpil Hwang of Korea University and co-workers, amalgamates the precision of atomic force microscopy with a diffusion limited current from a microscopic electrode.

Contact between the pen's tip and a working electrode creates a localised electroactive area for precise electrodeposition

At its tip, the pen has a microscopic hydrogel pyramid, the sharp apex of which is soaked in an electrolyte for electrochemical reactions. A nanometre-scale area for reactant mass transport results from contact between this tip and an ultramicroelectrode. Controlling this contact with a nanopositioning system regulates a faradaic reaction that enables electroplating to give precise nanostructures; in this case 3D structures of platinum were deposited on a gold electrode – some with dimensions less than 100nm.

To read the full article visit the Chemistry World website.

The paper is free to read in Nanoscale until 13 January 2015:

Hydrogel Pen for Electrochemical Reaction and Its Applications for 3D Printing
Hosuk Kang, Seongpil Hwang and Juhyoun Kwak, Nanoscale, 2015, DOI: 10.1039/C4NR06041E

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)

Nanoscale article featured in Chemistry World: Graphene springs into action

Researchers in China are hoping to expand the unconventional applications of graphene with their introduction of graphene springs that can function as actuators.

Springs are fundamental components in numerous electronic and mechanical systems. Most commercial springs are made of metal. Carbon-based springs, however, are less advanced, but have the potential to be a lightweight option if their poor elasticity can be tackled.

Now, graphene springs made by Liangti Qu and colleagues, at the Beijing Institute of Technology, succeed where traditional carbon-based springs have failed.

Interested to know more? Read the full news article by Jennifer Newton in Chemistry World here…

Read the article by Liangti Qu, Huhu Cheng, Yuan Liang, Fei Zhao, Yue Hu, Zelin Dong and Lan Jiang in Nanoscale:

Functional Graphene Springs for Responsive Actuation
Liangti Qu, Huhu Cheng, Yuan Liang, Fei Zhao, Yue Hu, Zelin Dong and Lan Jiang
DOI: 10.1039/C4NR03409K, Communication

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)

Biocompatible hydrogels for non-toxic conductive materials: Nanoscale article in Chemistry World

Implantable medical devices of the future could be built from a new material that is made by layering bacterial cellulose hydrogels with conducting polymers.

Bacterial cellulose (BC) is a naturally occurring polymer hydrogel that is flexible and known to respond to environmental changes. Guang Yang and co-workers at Huazhong University of Science and Technology in Wuhan, China, added a layer of conductive polymer polyaniline (PAni) onto a BC hydrogel to give a material that responds to electrical signals.

The base cellulose hydrogel is made by Gluconacetobacter xylinum bacteria. After purification, the hydrogel is soaked for 48 hours in a solution of salts and aniline monomers. The gel is then sandwiched between two electrodes, and applying an electrical current causes the monomers to form a polymer film layer.

Interested to know more? Read the full news article by Cally Haynes in Chemistry World here…

Read the article by Zhijun Shi, Ying Li, Xiuli Chen, Hongwei Han and Guang Yang in Nanoscale:

Double networks bacterial cellulose hydrogel to build a biology–device interface
Zhijun Shi, Ying Li, Xiuli Chen, Hongwei Han and Guang Yang
DOI: 10.1039/C3NR05214A, Paper

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)

Encryption at the flick of a light switch: Nanoscale article in Chemistry World

Scientists have designed a grid of light responsive colloidal particles to function as pixels that could be used to create barcodes for cryptographic data storage.

Photochromic dyes are used in films to respond to light, for example in self-dimming sunglasses. These dyes have two isomers, one forms in visible light and is transparent, the other forms in UV light and absorbs light, darkening the sunglasses. If a photochromic dye is placed in a film with a fluorescent dye, and the wavelength of the fluorescence is matched to that absorbed by the photochromic dye, the photochromic dye can be used to switch the fluorescence off and on when exposed to UV or visible light.

Clemens Weiß and his colleagues at the Max-Planck Institute for Polymer Research in Germany, have devised a way to use this kind of light triggered dye switch to store data. Encapsulating the photochromic/fluorescent dye pair inside polymer colloids traps the molecules together prolonging the lifetime of the ‘on’ or ‘off’ state for several days. Assembling these functional colloids within a monolayer of larger colloids creates a grid of fluorescent ‘colloidal pixels’. Shining UV light on chosen areas of the grid turns the pixels’ fluorescence off creating dark areas on the grid whilst leaving others fluorescent.

Interested to know more? Read the full news article by Emily Skinner in Chemistry World here…

Read the article by K. Bley, N. Sinatra, N. Vogel, K. Landfester and C. K. Weiss in Nanoscale:

Switching light with light – advanced functional colloidal monolayers
K. Bley, N. Sinatra, N. Vogel, K. Landfester and C. K. Weiss
DOI: 10.1039/C3NR04897G, Paper

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)

Patterning graphene onto complex surfaces: Nanoscale article in Chemistry World

Graphene could find use in next-generation flexible electronic devices thanks to scientists in Taiwan and the US who have developed a low cost and scalable method to pattern graphene onto 3D surfaces.
Graphical abstract: Scalable, flexible and high resolution patterning of CVD graphene

Flexible electronics are destined to transform the way we manufacture and interact with electronic devices. Graphene’s high electrical conductivity and mechanical stability could prove beneficial in flexible electronic circuits. However, despite its potential, graphene is typically only produced and patterned in research environments with economic barriers hampering its use in commercial applications.

Now, a group led by Mario Hofmann at National Cheng Kung University have demonstrated an easy and scalable approach to depositing high resolution graphene patterns onto surfaces.

Interested to know more? Read the full news article by Michael Parkin in Chemistry World here…

Read the article by Mario Hofmann, Ya-Ping Hsieh, Allen L. Hsu and Jing Kong in Nanoscale:

Scalable, flexible and high resolution patterning of CVD graphene
Mario Hofmann, Ya-Ping Hsieh, Allen L. Hsu and Jing Kong
DOI: 10.1039/C3NR04968J

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)

Silent labs for futuristic nanotechnology: Nanoscale article in Chemistry World

Scientists can now experiment at the atomic scale with unprecedented accuracy in new ‘silent’ laboratories in Switzerland. These labs are shielded against all possible forms of background disturbances – external vibrations, acoustic noise, electromagnetic fields and temperature fluctuations. It is hoped that the labs, devised by Emanuel Lörtscher and his team at IBM Zurich, will accommodate the demands of nanotechnology for the next 20–30 years.

When probing or building structures at the nanoscale, experimental readings are so tiny that they are easily drowned out by any background noise – without a well-proofed lab, someone using the lift next door could ruin your results.

Interested to know more? Read the full news article by Rowan Frame in Chemistry World here…

The labs were designed to screen all sources of background noise relevant to nanotechnology

Read the article by  E Lörtscher, D Widmer and B Gotsmann in Nanoscale:

Next-Generation Nanotechnology Laboratories with Simultaneous Reduction of all Relevant Disturbances
Emanuel Lörtscher, Daniel Widmer and Bernd Gotsmann  
DOI:
10.1039/C3NR03373B

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)

Next-generation vascular stents: Nanoscale article in Chemistry World

Vascular stents can be surgically inserted into blood vessels to treat atherosclerosis © Shutterstock

Scientists in the US and China have developed a biodegradable alloy for use in medical implants. The new alloy, called JDBM, mixes magnesium, neodymium, zinc and zirconium. JDBM degrades uniformly in physiological conditions so further surgery to remove implants made from it would not be necessary.

Atherosclerosis is a precursor to heart disease and occurs when artery walls thicken from cholesterol build-up. Surgical atherosclerosis treatment uses a mesh tube called a stent to restore blood flow in blocked blood vessels. While most currently used stents are non-degradable and require further surgery to remove them, stents made from JDBM by the teams of Rong Fan at Yale University and Guanyin Yuan at Shanghai Jiaotong University will degrade in the body so won’t need to be removed.

Interested to know more? Read the full news article by Emma Eley in Chemistry World here…

Read the article by L Mao et al. in Nanoscale:

Nanophasic biodegradation enhances durability and biocompatibility of magnesium alloys for the next-generation vascular stents
Lin Mao, Li Shen, Jialin Liu, Jian Zhang, Wenjiang Ding, Rong Fan and Guangyin Yuan
DOI: 10.1039/C3NR02912C

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)

Nanomagnets clean blood: Nanoscale article in Chemistry World

Nanoparticles that never have to enter the body can capture harmful components in blood, scientists in Switzerland have shown.

Removing unwanted molecules from the blood is the most direct way to cure or prevent many illnesses. An example of this approach is dialysis where small molecules like urea are filtered out to treat patients with renal failure. As this separation method is size-selective, larger noxious molecules or cells cannot be efficiently eliminated from the blood in this way.

Interested to know more? Read the full news article by Rowan Frame in Chemistry World here…

Read the article by  I K Herrmann et al. in Nanoscale:

Nanomagnet-based removal of lead and digoxin from living rats
Nanoscale, 2013, Accepted Manuscript
DOI: 10.1039/c3nr02468g

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)