Tag Archives: manganese

Nanoparticles from tattoo inks circulate through your body

English: Tattoo of Hand of Fatima,. Model: Casini. Date: 4 July 2017, 18:13:41. Source : Own work. Author: Stephencdickson.

For those who like their news in video format, there’s this Canadian Broadcasting Corporation (CBC) news item broadcast on Sep. 11, 2017 (after the commercials),

For those who like text and more detail, scientists at the European Synchrotron Radiation Facility (ESRF) have produced a study of the (at the nanoparticle scale) inks in tattoos. From a Sept. 12, 2017 news item on phys.org,

The elements that make up the ink in tattoos travel inside the body in micro and nanoparticle forms and reach the lymph nodes, according to a study published in Scientific Reports on 12 September [2017] by scientists from Germany and the ESRF, the European Synchrotron, Grenoble (France). It is the first time researchers have found analytical evidence of the transport of organic and inorganic pigments and toxic element impurities as well as in depth characterization of the pigments ex vivo in tattooed tissues. Two ESRF beamlines were crucial in this breakthrough.

A Sept. 12, 2017 ESRF press release (also on EurkeAlert), which originated the news item, explains further,

The reality is that little is known about the potential impurities in the colour mixture applied to the skin. Most tattoo inks contain organic pigments, but also include preservatives and contaminants like nickel, chromium, manganese or cobalt. Besides carbon black, the second most common ingredient used in tattoo inks is titanium dioxide (TiO2), a white pigment usually applied to create certain shades when mixed with colorants. Delayed healing, along with skin elevation and itching, are often associated with white tattoos, and by consequence with the use of TiO2. TiO2 is also commonly used in food additives, sun screens and paints. Scientists from the ESRF, the German Federal Institute for Risk Assessment, Ludwig-Maximilians University, and the Physikalisch-Technische Bundesanstalt have managed to get a very clear picture on the location of titanium dioxide once it gets in the tissue. This work was done on the ESRF beamlines ID21 and ID16B.

drawing tattookinetics.jpg

Translocation of tattoo particles from skin to lymph nodes. Upon injection of tattoo inks, particles can be either passively transported via blood and lymph fluids or phagocytized by immune cells and subsequently deposited in regional lymph nodes. After healing, particles are present in the dermis and in the sinusoids of the draining lymph nodes. Credits: C. Seim.

The hazards that potentially derive from tattoos were, until now, only investigated by chemical analysis of the inks and their degradation products in vitro. “We already knew that pigments from tattoos would travel to the lymph nodes because of visual evidence: the lymph nodes become tinted with the colour of the tattoo. It is the response of the body to clean the site of entrance of the tattoo. What we didn’t know is that they do it in a nano form, which implies that they may not have the same behaviour as the particles at a micro level. And that is the problem: we don’t know how nanoparticles react”, explains Bernhard Hesse, one of the two first authors of the study (together with Ines Schreiver, from the German Federal Institute for Risk Assessment) and ESRF visiting scientist.

titaniumdistribution.jpg

Particle mapping and size distribution of different tattoo pigment elements.  a, d) Ti and the Br containing pigment phthalocyanine green 36 are located next to each other. b, e) Log scale mappings of Ti, Br and Fe in the same areas as displayed in a) and d) reveal primary particle sizes of different pigment species. c, f) Magnifications of the indicated areas in b) and e), respectively. Credits: C. Seim.

X-ray fluorescence measurements on ID21 allowed the team to locate titanium dioxide at the micro and nano range in the skin and the lymphatic environment. They found a broad range of particles with up to several micrometres in size in human skin, but only smaller (nano) particles transported to the lymph nodes. This can lead to the chronic enlargement of the lymph nodes and lifelong exposure. Scientists also used the technique of Fourier transform infrared spectroscopy to assess biomolecular changes in the tissues in the proximity of the tattoo particles.

ESRF16_Tattoo-1low.jpg

Ines Schreiver doing experiments on ID16B with Julie Villanova. Credits: B. Hesse.

Altogether the scientists report strong evidence for both migration and long-term deposition of toxic elements and tattoo pigments as well as for conformational alterations of biomolecules that are sometimes linked to cutaneous adversities upon tattooing.

Then next step for the team is to inspect further samples of patients with adverse effects in their tattoos in order to find links with chemical and structural properties of the pigments used to create these tattoos.

Here’s a link to and  a citation for the paper,

Synchrotron-based ν-XRF mapping and μ-FTIR microscopy enable to look into the fate and effects of tattoo pigments in human skin by Ines Schreiver, Bernhard Hesse, Christian Seim, Hiram Castillo-Michel, Julie Villanova, Peter Laux, Nadine Dreiack, Randolf Penning, Remi Tucoulou, Marine Cotte, & Andreas Luch. Scientific Reports 7, Article number: 11395 (2017) doi:10.1038/s41598-017-11721-z Published online: 12 September 2017

This paper is open access.

Nontoxic, biodegradable orthopedic implant for damaged bones

Unlike most of the science items on phys.org this April 14, 2017 news item is not a publication announcement,

Purdue University researchers are developing a nontoxic, biodegradable orthopedic implant that could be safely absorbed by the body after providing adequate support to damaged bones.

The development of the technology originated in the lab of Lia Stanciu, a professor of materials engineering at Purdue in 2009. The technology could eliminate the need for a second surgery to remove conventional hardware.

“Currently, most implants use stainless steel and titanium alloys for strength. This can cause long-term change in the mechanics of the specific region and eventual long-term deterioration,” Stanciu said. “Additionally medical operations that require an orthopedic implant must be followed-up with a second surgery to remove the implant or the accompanying hardware of the implant resulting in higher medical costs and an increased risk of complications.”

An April 13, 2017 Purdue University news release, which originated the news item, provides a bit more detail and a hint as to what may have occasioned the news release,

Co-inventors of the technology are Stanciu; Eric Nauman, a professor in Purdue’s College of Engineering and director of the College of Engineering Honors Programs; Michael J Heiden, a PhD candidate; and Mahdi Dehestani, a graduate research assistant, both in Purdue’s School of Materials Engineering.

Nauman said the resorbable metal technology provides superior properties compared to conventional metals.

“The implant has high porosity, which is empty space in the material, in which optimal vascular invasion can occur. This provides a way for cells to optimally absorb the material,” he said. “Our technology is able to provide short-term fixation but eliminate the need for long-term hardware such as titanium or stainless steel that may require second surgeries to be retrieved,”

The orthopedic implant also uses manganese, which provides a better degradation rate, Stanciu added.

“Current resorbable metals are made with magnesium; however, this provides many adverse side effects to the body and degrades very quickly,” she said. “We decided to use manganese instead of magnesium. Through studies we found that we can control the degradation rates from 22 millimeters per year to 1.2 millimeters per year pretty consistently. We also saw that manganese has a very good corrosion rate over time.”

Nauman said the technology still exhibits the usual benefits associated with using biomaterials.

“With this technology we are able to tailor the surfaces such as de-alloying the surface to provide a better material for cells to grab on to and grow,” he said. “We were also able to show that we could control cell attachment proliferation, an increase of the number of cells. Our technology still has all these usual benefits in addition to controlling the degradation rates of the metals.”

The Purdue Research Foundation’s Office of Technology Commercialization has patented the technology and it is available for license. For information call 765-588-3470 or email innovation@prf.org.

I believe they’re looking for a commercial partner of some kind.

Refining metals more sustainably

We don’t just extract and refine metals from the earth, increasingly, we extract and refine them from consumer goods. Researchers from McGill University (Montréal, Québec, Canada) have devised a ‘greener’ technique to do this. From a June 7, 2017 McGill University news release (received via email and also on EurekAlert),

A team of chemists in Canada has developed a way to process metals without using toxic solvents and reagents.

The system, which also consumes far less energy than conventional techniques, could greatly shrink the environmental impact of producing metals from raw materials or from post-consumer electronics.

“At a time when natural deposits of metals are on the decline, there is a great deal of interest in improving the efficiency of metal refinement and recycling, but few disruptive technologies are being put forth,” says Jean-Philip Lumb, an associate professor in McGill University’s Department of Chemistry. “That’s what makes our advance so important.”

The discovery stems from a collaboration between Lumb and Tomislav Friscic at McGill in Montreal, and Kim Baines of Western University in London, Ont. In an article published recently in Science Advances, the researchers outline an approach that uses organic molecules, instead of chlorine and hydrochloric acid, to help purify germanium, a metal used widely in electronic devices. Laboratory experiments by the researchers have shown that the same technique can be used with other metals, including zinc, copper, manganese and cobalt.

The research could mark an important milestone for the “green chemistry” movement, which seeks to replace toxic reagents used in conventional industrial manufacturing with more environmentally friendly alternatives. Most advances in this area have involved organic chemistry – the synthesis of carbon-based compounds used in pharmaceuticals and plastics, for example.

“Applications of green chemistry lag far behind in the area of metals,” Lumb says. “Yet metals are just as important for sustainability as any organic compound. For example, electronic devices require numerous metals to function.”

Taking a page from biology

There is no single ore rich in germanium, so it is generally obtained from mining operations as a minor component in a mixture with many other materials. Through a series of processes, that blend of matter can be reduced to germanium and zinc.

“Currently, in order to isolate germanium from zinc, it’s a pretty nasty process,” Baines explains. The new approach developed by the McGill and Western chemists “enables you to get germanium from zinc, without those nasty processes.”

To accomplish this, the researchers took a page from biology. Lumb’s lab for years has conducted research into the chemistry of melanin, the molecule in human tissue that gives skin and hair their color. Melanin also has the ability to bind to metals. “We asked the question: ‘Here’s this biomaterial with exquisite function, would it be possible to use it as a blueprint for new, more efficient technologies?'”

The scientists teamed up to synthesize a molecule that mimics some of the qualities of melanin. In particular, this “organic co-factor” acts as a mediator that helps to extract germanium at room temperature, without using solvents.

Next step: industrial scale

The system also taps into Friscic’s expertise in mechanochemistry, an emerging branch of chemistry that relies on mechanical force – rather than solvents and heat – to promote chemical reactions. Milling jars containing stainless-steel balls are shaken at high speeds to help purify the metal.

“This shows how collaborations naturally can lead to sustainability-oriented innovation,” Friscic says. “Combining elegant new chemistry with solvent-free mechanochemical techniques led us to a process that is cleaner by virtue of circumventing chlorine-based processing, but also eliminates the generation of toxic solvent waste”

The next step in developing the technology will be to show that it can be deployed economically on industrial scales, for a range of metals.

“There’s a tremendous amount of work that needs to be done to get from where we are now to where we need to go,” Lumb says. “But the platform works on many different kinds of metals and metal oxides, and we think that it could become a technology adopted by industry. We are looking for stakeholders with whom we can partner to move this technology forward.”

Here’s a link to and a citation for the paper,

A chlorine-free protocol for processing germanium by Martin Glavinovic, Michael Krause, Linju Yang, John A. McLeod, Lijia Liu, Kim M. Baines, Tomislav Friščić, and Jean-Philip Lumb. Science Advances 05 May 2017: Vol. 3, no. 5, e1700149 DOI: 10.1126/sciadv.1700149

This paper is open access.

ETA June 9, 2017 at 1700 hours PDT: I have to give them marks for creativity. Here’s the image being used to illustrate the work,

Caption: Strategy for reducing the environmental impact of a refining process: replace hazardous chemicals with more benign and recyclable compounds. Credit: Michael J. Krause (Western University)

South Africa, energy, and nanotechnology

South African academics Nosipho Moloto, Associate Professor, Department of Chemistry, University of the Witwatersrand and Siyabonga P. Ngubane, Lecturer in Chemistry, University of the Witwatersrand have written a Feb. 17, 2016 article for The Conversation (also available on the South African Broadcasting Corporation website) about South Africa’s energy needs and its nanotechnology efforts (Note: Links have been removed),

Energy is an economic driver of both developed and developing countries. South Africa over the past few years has faced an energy crisis with rolling blackouts between 2008 and 2015. Part of the problem has been attributed to mismanagement by the state-owned utility company Eskom, particularly the shortcomings of maintenance plans on several plants.

But South Africa has two things going for it that could help it out of its current crisis. By developing a strong nanotechnology capability and applying this to its rich mineral reserves the country is well-placed to develop new energy technologies.

Nanotechnology has already shown that it has the potential to alleviate energy problems. …

It can also yield materials with new properties and the miniaturisation of devices. For example, since the discovery of graphene, a single atomic layer of graphite, several applications in biological engineering, electronics and composite materials have been identified. These include economic and efficient devices like solar cells and lithium ion secondary batteries.

Nanotechnology has seen an incredible increase in commercialisation. Nearly 10,000 patents have been filed by large corporations since its beginning in 1991. There are already a number of nanotechnology products and solutions on the market. Examples include Miller’s beer bottling composites, Armor’s N-Force line bulletproof vests and printed solar cells produced by Nanosolar – as well as Samsung’s nanotechnology television.

The advent of nanotechnology in South Africa began with the South African Nanotechnology Initiative in 2002. This was followed by the a [sic] national nanotechnology strategy in 2003.

The government has spent more than R450 million [Rand] in nanotechnology and nanosciences research since 2006. For example, two national innovation centres have been set up and funding has been made available for equipment. There has also been flagship funding.

The country could be globally competitive in this field due to the infancy of the technology. As such, there are plenty of opportunities to make novel discoveries in South Africa.

Mineral wealth

There is another major advantage South Africa has that could help diversify its energy supply. It has an abundance of mineral wealth with an estimated value of US$2.5 trillion. The country has the world’s largest reserves of manganese and platinum group metals. It also has massive reserves of gold, diamonds, chromite ore and vanadium.

Through beneficiation and nanotechnology these resources could be used to cater for the development of new energy technologies. Research in beneficiation of minerals for energy applications is gaining momentum. For example, Anglo American and the Department of Science and Technology have embarked on a partnership to convert hydrogen into electricity.

The Council for Scientific and Industrial research also aims to develop low cost lithium ion batteries and supercapacitors using locally mined manganese and titanium ores. There is collaborative researchto use minerals like gold to synthesize nanomaterials for application in photovoltaics.

The current photovoltaic market relies on importing solar cells or panels from Europe, Asia and the US for local assembly to produce arrays. South African UV index is one of the highest in the world which reduces the lifespan of solar panels. The key to a thriving and profitable photovoltaic sector therefore lies in local production and research and development to support the sector.

It’s worth reading the article in its entirety if you’re interested in a perspective on South Africa’s energy and nanotechnology efforts.