Tag Archives: Empa

Nanocellulosic 3D-printed ears

It’s been a while since I’ve had a story abut cellulose nanocrystals (CNC) and this one comes from Switzerland’s Empa (Swiss Federal Laboratories for Materials Science and Technology) in a January 15, 2019 news item on Nanowerk (Note: A link has been removed),

Cellulose obtained from wood has amazing material properties. Empa researchers are now equipping the biodegradable material with additional functionalities to produce implants for cartilage diseases using 3D printing (ACS Nano, “Dynamics of Cellulose Nanocrystal Alignment during 3D Printing”).

It all starts with an ear. Empa researcher Michael Hausmann removes the object shaped like a human ear from the 3D printer and explains: “In viscous state cellulose nanocrystals can easily be shaped together with nother biopolymers into complex 3-dimensional structures using a 3D printer, such as the Bioplotter.”

Once cross-linked, the structures remain stable despite their soft mechanical properties. Hausmann is currently investigating the characteristics of the nanocellulose composite hydrogels in order to further optimize their stability as well as the printing process. The researcher already used X-ray analysis to determine how cellulose is distributed and organized within the printed structures.

At this point in time the printed ear is entirely and solely made of cellulose nanocrystals and a biopolymer. However, the objective is to incorporate both human cells and therapeutics into the base structure in order to produce biomedical implants.

Here’s one of the researchers (Michael Hausmann) showing off their ‘ear’,

A 3D-printed ear: Empa researcher Michael Hausmann uses nanocellulose as the basis for novel implants (Image: Empa)

Doesn’t look like much does, eh? It’s scaffolding or, you could say, a kind of skeleton and a January 15, 2019 Empa press release, which originated the news item, describes it and explains how it will house new cells,

A new project is currently underway, looking into how chondrocytes (cartilage cells) can be integrated into the scaffold to yield artificial cartilage tissue. As soon as the colonization of the hydrogel with cells is established, nanocellulose based composites in the shape of an ear could serve as an implant for children with an inherited auricular malformation as for instance, in microtia, where the external ears are only incompletely developed. A reconstruction of the auricle can esthetically and medically correct the malformation; otherwise the hearing ability can be severely impaired. In the further course of the project, cellulose nanocrystals containing hydrogels will also be used for the replacement of articular cartilage (e.g. knee) in cases of joint wear due to, for example, chronic arthritis.

Once the artificial tissue has been implanted in the body, the biodegradable polymer material is expected to degrade over time. The cellulose itself is not degradable in the body, but biocompatible. However, it is not only its biocompatibility that makes nanocellulose the perfect material for implant scaffolds. “It is also the mechanical performance of cellulose nanocrystals that make them such promising candidates because the tiny but highly stable fibers can extremely well reinforce the produced implant,” said Hausmann.

Moreover, nanocellulose allows the incorporation of various functions by chemical modifications into the viscous hydrogel. Thus, the structure, the mechanical properties and the interactions of the nanocellulose with its environment can be specifically tailored to the desired end product. “For instance, we can incorporate active substances that promote the growth of chondrocytes or that sooth joint inflammation into the hydrogel,” says the Empa researcher.

And last but not least, as raw material cellulose is the most abundant natural polymer on earth. Therefore, the use of cellulose nanocrystals not only benefits from the mere elegance of the novel process but also from the availability of the raw material.

The white nanocellulose ear lies glossy on the glass carrier. Just out of the Bioplotter, it is already robust and dimensionally stable. Hausmann can give the go-ahead for the next steps. 

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

Dynamics of Cellulose Nanocrystal Alignment during 3D Printing by Michael K. Hausmann, Patrick A. Rühs, Gilberto Siqueira, Jörg Läuger, Rafael Libanori, Tanja Zimmermann, and André R. Studart. ACS Nano, 2018, 12 (7), pp 6926–6937 DOI: 10.1021/acsnano.8b02366 Publication Date (Web): July 5, 2018

Copyright © 2018 American Chemical Society

This paper is behind a paywall.

The Swiss come to a better understanding of nanomaterials

Just to keep things interesting, after the report suggesting most of the information that the OECD (Organization for Economic Cooperation and Development) has on nanomaterials is of little value for determining risk (see my April 5, 2017 posting for more) the Swiss government has released a report where they claim an improved understanding of nanomaterials than they previously had due to further research into the matter. From an April 6, 2017 news item on Nanowerk,

In the past six years, the [Swiss] National Research Programme “Opportunities and Risks of Nanomaterials” (NRP 64) intensively studied the development, use, behaviour and degradation of engineered nanomaterials, including their impact on humans and on the environment.

Twenty-three research projects on biomedicine, the environment, energy, construction materials and food demonstrated the enormous potential of engineered nanoparticles for numerous applications in industry and medicine. Thanks to these projects we now know a great deal more about the risks associated with nanomaterials and are therefore able to more accurately determine where and how they can be safely used.

An April 6, 2017 Swiss National Science Foundation press release, which originated the news item, expands on the theme,

“One of the specified criteria in the programme was that every project had to examine both the opportunities and the risks, and in some cases this was a major challenge for the researchers,” explains Peter Gehr, President of the NRP 64 Steering Committee.

One development that is nearing industrial application concerns a building material strengthened with nanocellulose that can be used to produce a strong but lightweight insulation material. Successful research was also carried out in the area of energy, where the aim was to find a way to make lithium-ion batteries safer and more efficient.

Promising outlook for nanomedicine

A great deal of potential is predicted for the field of nanomedicine. Nine of the 23 projects in NRP 64 focused on biomedical applications of nanoparticles. These include their use for drug delivery, for example in the fight against viruses, or as immune modulators in a vaccine against asthma. Another promising application concerns the use of nanomagnets for filtering out harmful metallic substances from the blood. One of the projects demonstrated that certain nanoparticles can penetrate the placenta barrier, which points to potential new therapy options. The potential of cartilage and bone substitute materials based on nanocellulose or nanofibres was also studied.

The examination of potential health risks was the focus of NRP 64. A number of projects examined what happens when nanoparticles are inhaled, while two focused on ingestion. One of these investigated whether the human gut is able to absorb iron more efficiently if it is administered in the form of iron nanoparticles in a food additive, while the other studied silicon nanoparticles as they occur in powdered condiments. It was ascertained that further studies will be required in order to determine the doses that can be used without risking an inflammatory reaction in the gut.

What happens to engineered nanomaterials in the environment?

The aim of the seven projects focusing on environmental impact was to gain a better understanding of the toxicity of nanomaterials and their degradability, stability and accumulation in the environment and in biological systems. Here, the research teams monitored how engineered nanoparticles disseminate along their lifecycle, and where they end up or how they can be discarded.

One of the projects established that 95 per cent of silver nanoparticles that are washed out of textiles are collected in sewage treatment plants, while the remaining particles end up in sewage sludge, which in Switzerland is incinerated. In another project a measurement device was developed to determine how aquatic microorganisms react when they come into contact with nanoparticles.

Applying results and making them available to industry

“The findings of the NRP 64 projects form the basis for a safe application of nanomaterials,” says Christoph Studer from the Federal Office of Public Health. “It has become apparent that regulatory instruments such as testing guidelines will have to be adapted at both national and international level.” Studer has been closely monitoring the research programme in his capacity as the Swiss government’s representative in NRP 64. In this context, the precautionary matrix developed by the government is an important instrument by means of which companies can systematically assess the risks associated with the use of nanomaterials in their production processes.

The importance of standardised characterisation and evaluation of engineered nanomaterials was highlighted by the close cooperation among researchers in the programme. “The research network that was built up in the framework of NRP 64 is functioning smoothly and needs to be further nurtured,” says Professor Bernd Nowack from Empa, who headed one of the 23 projects.

The results of NRP 64 show that new key technologies such as the use of nanomaterials need to be closely monitored through basic research due to the lack of data on its long-term effects. As Peter Gehr points out, “We now know a lot more about the risks of nanomaterials and how to keep them under control. However, we need to conduct additional research to learn what happens when humans and the environment are exposed to engineered nanoparticles over longer periods, or what happens a long time after a one-off exposure.”

You can find out more about the Opportunities and Risks of Nanomaterials; National Research Programme (NRP 64) here.

Cientifica’s latest smart textiles and wearable electronics report

After publishing a report on wearable technology in May 2016 (see my June 2, 2016 posting), Cientifica has published another wearable technology report, this one is titled, Smart Textiles and Wearables: Markets, Applications and Technologies. Here’s more about the latest report from the report order page,

“Smart Textiles and Wearables: Markets, Applications and Technologies” examines the markets for textile based wearable technologies, the companies producing them and the enabling technologies. This is creating a 4th industrial revolution for the textiles and fashion industry worth over $130 billion by 2025.

Advances in fields such as nanotechnology, organic electronics (also known as plastic electronics) and conducting polymers are creating a range of textile–based technologies with the ability to sense and react to the world around them.  This includes monitoring biometric data such as heart rate, the environmental factors such as temperature and The presence of toxic gases producing real time feedback in the form of electrical stimuli, haptic feedback or changes in color.

The report identifies three distinct generations of textile wearable technologies.

First generation is where a sensor is attached to apparel and is the approach currently taken by major sportswear brands such as Adidas, Nike and Under Armour
Second generation products embed the sensor in the garment as demonstrated by products from Samsung, Alphabet, Ralph Lauren and Flex.
In third generation wearables the garment is the sensor and a growing number of companies including AdvanPro, Tamicare and BeBop sensors are making rapid progress in creating pressure, strain and temperature sensors.

Third generation wearables represent a significant opportunity for new and established textile companies to add significant value without having to directly compete with Apple, Samsung and Intel.

The report predicts that the key growth areas will be initially sports and wellbeing

followed by medical applications for patient monitoring. Technical textiles, fashion and entertainment will also be significant applications with the total market expected to rise to over $130 billion by 2025 with triple digit compound annual growth rates across many applications.

The rise of textile wearables also represents a significant opportunity for manufacturers of the advanced materials used in their manufacture. Toray, Panasonic, Covestro, DuPont and Toyobo are already suppling the necessary materials, while researchers are creating sensing and energy storage technologies, from flexible batteries to graphene supercapacitors which will power tomorrows wearables. The report details the latest advances and their applications.

This report is based on an extensive research study of the wearables and smart textile markets backed with over a decade of experience in identifying, predicting and sizing markets for nanotechnologies and smart textiles. Detailed market figures are given from 2016-2025, along with an analysis of the key opportunities, and illustrated with 139 figures and 6 tables.

The September 2016 report is organized differently and has a somewhat different focus from the report published in May 2016. Not having read either report, I’m guessing that while there might be a little repetition, you might better consider them to be companion volumes.

Here’s more from the September 2016 report’s table of contents which you can download from the order page (Note: The formatting has been changed),

SMART TEXTILES AND WEARABLES:
MARKETS, APPLICATIONS AND
TECHNOLOGIES

Contents  1
List of Tables  4
List of Figures  4
Introduction  8
How to Use This Report  8
Wearable Technologies and the 4Th Industrial Revolution  9
The Evolution of Wearable Technologies  10
Defining Smart Textiles  15
Factors Affecting The Adoption of Smart Textiles for Wearables  18
Cost  18
Accuracy  18
On Shoring  19
Power management  19
Security and Privacy  20
Markets  21
Total Market Growth and CAGR  21
Market Growth By Application  21
Adding Value To Textiles Through Technology  27
How Nanomaterials Add Functionality and Value  31
Business Models  33
Applications  35
Sports and Wellbeing  35
1st Generation Technologies  35
Under Armour Healthbox Wearables  35
Adidas MiCoach  36
Sensoria  36
EMPA’s Long Term Research  39
2nd Generation Technologies  39
Google’s Project Jacquard  39
Samsung Creative Lab  43
Microsoft Collaborations  44
Intel Systems on a Chip  44
Flex (Formerly Flextronics) and MAS Holdings  45
Jiobit  46
Asensei Personal Trainer  47
OmSignal Smart Clothing  48
Ralph Lauren PoloTech  49
Hexoskin Performance Management  50
Jabil Circuit Textile Heart Monitoring  51
Stretch Sense Sensors  52
NTT Data and Toray  54
Goldwin Inc. and DoCoMo  55
SupaSpot Inc Smart Sensors  55
Wearable Experiments and Brand Marketing  56
Wearable Life Sciences Antelope  57
Textronics NuMetrex  59
3rd Generation Technologies  60
AdvanPro Pressure Sensing Shoes  60
Tamicare 3D printed Wearables with Integrated Sensors  62
AiQ Smart Clothing Stainless Steel Yarns  64
Flex Printed Inks And Conductive Yarns  66
Sensing Tech Conductive Inks  67
EHO Textiles Body Motion Monitoring  68
Bebop Sensors Washable E-Ink Sensors  70
Fraunhofer Institute for Silicate Research Piezolectric Polymer
Sensors  71
CLIM8 GEAR Heated Textiles  74
VTT Smart Clothing Human Thermal Model  74
ATTACH (Adaptive Textiles Technology with Active Cooling and Heating) 76
Energy Storage and Generation  78
Intelligent Textiles Military Uniforms  78
BAE Systems Broadsword Spine  79
Stretchable Batteries  80
LG Chem Cable Batteries  81
Supercapacitors  83
Swinburne Graphene Supercapacitors  83
MIT Niobium Nanowire Supercapacitors  83
Energy Harvesting  86
Kinetic  86
StretchSense Energy Harvesting Kit  86
NASA Environmental Sensing Fibers  86
Solar  87
Powertextiles  88
Sphelar Power Corp Solar Textiles  88
Ohmatex and Powerweave  89
Fashion  89
1st Generation Technologies  92
Cute Circuit LED Couture  92
MAKEFASHION LED Couture  94
2nd Generation Technologies  94
Covestro Luminous Clothing  94
3rd Generation Technologies  96
The Unseen Temperature Sensitive Dyes  96
Entertainment  98
Wearable Experiments Marketing  98
Key Technologies 100
Circuitry  100
Conductive Inks for Fabrics  100
Conductive Ink For Printing On Stretchable Fabrics  100
Creative Materials Conductive Inks And Adhesives  100
Dupont Stretchable Electronic Inks  101
Aluminium Inks From Alink Co  101
Conductive Fibres  102
Circuitex Silver Coated Nylon  102
Textronics Yarns and Fibres  102
Novonic Elastic Conductive Yarn  103
Copper Coated Polyacrylonitrile (PAN) Fibres  103
Printed electronics  105
Covestro TPU Films for Flexible Circuits  105
Sensors  107
Electrical  107
Hitoe  107
Cocomi  108
Panasonic Polymer Resin  109
Cardiac Monitoring  110
Mechanical  113
Strain  113
Textile-Based Weft Knitted Strain Sensors  113
Chain Mail Fabric for Smart Textiles  113
Nano-Treatment for Conductive Fiber/Sensors 115
Piezoceramic materials  116
Graphene-Based Woven Fabric  117
Pressure Sensing  117
LG Innotek Flexible Textile Pressure Sensors  117
Hong Kong Polytechnic University Pressure Sensing Fibers  119
Conductive Polymer Composite Coatings  122
Printed Textile Sensors To Track Movement  125
Environment  127
Photochromic Textiles  127
Temperature  127
Sefar PowerSens  127
Gasses & Chemicals  127
Textile Gas Sensors  127
Energy  130
Storage  130
Graphene Supercapacitors  130
Niobium Nanowire Supercapacitors  130
Stretchy supercapacitors  132
Energy Generation  133
StretchSense Energy Harvesting Kit  133
Piezoelectric Or Thermoelectric Coated Fibres  134
Optical  137
Light Emitting  137
University of Manchester Electroluminescent Inks and Yarns 137
Polyera Wove  138
Companies Mentioned  141
List of Tables
Table 1 CAGR by application  22
Table 2 Value of market by application 2016-25 (millions USD)  24
Table 3 % market share by application  26
Table 4 CAGR 2016-25 by application  26
Table 5 Technology-Enabled Market Growth in Textile by Sector (2016-22) 28
Table 6 Value of nanomaterials by sector 2016-22 ($ Millions)  33
List of Figures
Figure 1 The 4th Industrial Revolution (World Economic Forum)  9
Figure 2 Block Diagram of typical MEMS digital output motion sensor: ultra
low-power high performance 3-axis “femto” accelerometer used in
fitness tracking devices.  11
Figure 3 Interior of Fitbit Flex device (from iFixit)  11
Figure 4 Internal layout of Fitbit Flex. Red is the main CPU, orange is the
BTLE chip, blue is a charger, yellow is the accelerometer (from iFixit)  11
Figure 5 Intel’s Curie processor stretches the definition of ‘wearable’  12
Figure 6 Typical Textile Based Wearable System Components  13
Figure 7 The Chromat Aeros Sports Bra “powered by Intel, inspired by wind, air and flight.”  14
Figure 8 The Evolution of Smart textiles  15
Figure 9 Goldwin’s C2fit IN-pulse sportswear using Toray’s Hitoe  16
Figure 10 Sensoglove reads grip pressure for golfers  16
Figure 11 Textile Based Wearables Growth 2016-25(USD Millions)  21
Figure 12 Total market for textile based wearables 2016-25 (USD Millions)  22
Figure 13 Health and Sports Market Size 2016-20 (USD Millions)  23
Figure 14 Health and Sports Market Size 2016-25 (USD Millions)  23
Figure 15 Critical steps for obtaining FDA medical device approval  25
Figure 16 Market split between wellbeing and medical 2016-25  26
Figure 17 Current World Textile Market by Sector (2016)  27
Figure 18 The Global Textile Market By Sector ($ Millions)  27
Figure 19 Compound Annual Growth Rates (CAGR) by Sector (2016-25)  28
Figure 20 The Global Textile Market in 2022  29
Figure 21 The Global Textile Market in 2025  30
Figure 22 Textile Market Evolution (2012-2025)  30
Figure 23 Total Value of Nanomaterials in Textiles 2012-2022 ($ Millions)  31
Figure 24 Value of Nanomaterials in Textiles by Sector 2016-2025 ($ Millions) 32
Figure 25 Adidas miCoach Connect Heart Rate Monitor  36
Figure 26 Sensoria’s Hear[t] Rate Monitoring Garments . 37
Figure 27 Flexible components used in Google’s Project Jacquard  40
Figure 28 Google and Levi’s Smart Jacket  41
Figure 29 Embedded electronics Google’s Project Jacquard  42
Figure 30 Samsung’s WELT ‘smart’ belt  43
Figure 31 Samsung Body Compass at CES16  44
Figure 32 Lumo Run washable motion sensor  45
Figure 33 OMSignal’s Smart Bra  49
Figure 34 PoloTech Shirt from Ralph Lauren  50
Figure 35 Hexoskin Data Acquisition and Processing  51
Figure 36 Peak+™ Hear[t] Rate Monitoring Garment  52
Figure 37 StretchSense CEO Ben O’Brien, with a fabric stretch sensor  53
Figure 38 C3fit Pulse from Goldwin Inc  55
Figure 39 The Antelope Tank-Top  58
Figure 40 Sportswear with integrated sensors from Textronix  60
Figure 41 AdvanPro’s pressure sensing insoles  61
Figure 42 AdvanPro’s pressure sensing textile  62
Figure 43 Tamicare 3D Printing Sensors and Apparel  63
Figure 44 Smart clothing using stainless steel yarns and textile sensors from AiQ  65
Figure 45 EHO Smart Sock  69
Figure 46 BeBop Smart Car Seat Sensor  71
Figure 47 Non-transparent printed sensors from Fraunhofer ISC  73
Figure 48 Clim8 Intelligent Heat Regulating Shirt  74
Figure 49 Temperature regulating smart fabric printed at UC San Diego  76
Figure 50 Intelligent Textiles Ltd smart uniform  79
Figure 51 BAE Systems Broadsword Spine  80
Figure 52 LG Chem cable-shaped lithium-ion battery powers an LED display even when twisted and strained  81
Figure 53 Supercapacitor yarn made of niobium nanowires  84
Figure 54 Sphelar Textile  89
Figure 55 Sphelar Textile Solar Cells  89
Figure 56 Katy Perry wears Cute Circuit in 2010  91
Figure 57 Cute Circuit K Dress  93
Figure 58 MAKEFASHION runway at the Brother’s “Back to Business” conference, Nashville 2016  94
Figure 59 Covestro material with LEDs are positioned on formable films made from thermoplastic polyurethane (TPU).  95
Figure 60 Unseen headpiece, made of 4000 conductive Swarovski stones, changes color to correspond with localized brain activity  96
Figure 61 Eighthsense a coded couture piece.  97
Figure 62 Durex Fundawear  98
Figure 63 Printed fabric sensors from the University of Tokyo  100
Figure 64 Tony Kanaan’s shirt with electrically conductive nano-fibers  107
Figure 65 Panasonic stretchable resin technology  109
Figure 66 Nanoflex moniroring system  111
Figure 67 Knitted strain sensors  113
Figure 68 Chain Mail Fabric for Smart Textiles  114
Figure 69 Electroplated Fabric  115
Figure 70 LG Innotek flexible textile pressure sensors  118
Figure 71 Smart Footwear installed with fabric sensors. (Credit: Image courtesy of The Hong Kong Polytechnic University)  120
Figure 72 SOFTCEPTOR™ textile strain sensors  122
Figure 73 conductive polymer composite coating for pressure sensing  123
Figure 74 Fraunhofer ISC_ printed sensor  125
Figure 75 The graphene-coated yarn sensor. (Image: ETRI)  128
Figure 76 Supercapacitor yarn made of niobium nanowires  131
Figure 77 StretchSense Energy Harvesting Kit  134
Figure 78 Energy harvesting textiles at the University of Southampton  135
Figure 79 Polyera Wove Flexible Screen  139

If you compare that with the table of contents for the May 2016 report in my June 2, 2016 posting, you can see the difference.

Here’s one last tidbit, a Sept. 15, 2016 news item on phys.org highlights another wearable technology report,

Wearable tech, which was seeing sizzling sales growth a year ago [2015], is cooling this year amid consumer hesitation over new devices, a survey showed Thursday [Sept. 15, 2016].

The research firm IDC said it expects global sales of wearables to grow some 29.4 percent to some 103 million units in 2016.

That follows 171 percent growth in 2015, fueled by the launch of the Apple Watch and a variety of fitness bands.

“It is increasingly becoming more obvious that consumers are not willing to deal with technical pain points that have to date been associated with many wearable devices,” said IDC analyst Ryan Reith.

So-called basic wearables—including fitness bands and other devices that do not run third party applications—will make up the lion’s share of the market with some 80.7 million units shipped this year, according to IDC.

According to IDC, it seems that the short term does not promise the explosive growth of the previous year but that new generations of wearable technology, according to both IDC and Cientifica, offer considerable promise for the market.

New model to track flow of nanomaterials through our air, earth, and water

Just how many tons of nanoparticles are making their way through the environment? Scientists at the Swiss Federal Laboratories for Materials Science and Technology (Empa) have devised a new model which could help answer that question. From a May 12, 2016 news item on phys.org,

Carbon nanotubes remain attached to materials for years while titanium dioxide and nanozinc are rapidly washed out of cosmetics and accumulate in the ground. Within the National Research Program “Opportunities and Risks of Nanomaterials” (NRP 64) a team led by Empa scientist Bernd Nowack has developed a new model to track the flow of the most important nanomaterials in the environment.

A May 12, 2016 Empa press release by Michael Hagmann, which also originated the news item, provides more detail such as an estimated tonnage for titanium dioxide nanoparticles produced annually in Europe,

How many man-made nanoparticles make their way into the air, earth or water? In order to assess these amounts, a group of researchers led by Bernd Nowack from Empa, the Swiss Federal Laboratories for Materials Science and Technology, has developed a computer model as part of the National Research Program “Opportunities and Risks of Nanomaterials” (NRP 64). “Our estimates offer the best available data at present about the environmental accumulation of nanosilver, nanozinc, nano-tinanium dioxide and carbon nanotubes”, says Nowack.

In contrast to the static calculations hitherto in use, their new, dynamic model does not just take into account the significant growth in the production and use of nanomaterials, but also makes provision for the fact that different nanomaterials are used in different applications. For example, nanozinc and nano-titanium dioxide are found primarily in cosmetics. Roughly half of these nanoparticles find their way into our waste water within the space of a year, and from there they enter into sewage sludge. Carbon nanotubes, however, are integrated into composite materials and are bound in products such as which are immobilized and are thus found for example in tennis racquets and bicycle frames. It can take over ten years before they are released, when these products end up in waste incineration or are recycled.

39,000 metric tons of nanoparticles

The researchers involved in this study come from Empa, ETH Zurich and the University of Zurich. They use an estimated annual production of nano-titanium dioxide across Europe of 39,000 metric tons – considerably more than the total for all other nanomaterials. Their model calculates how much of this enters the atmosphere, surface waters, sediments and the earth, and accumulates there. In the EU, the use of sewage sludge as fertilizer (a practice forbidden in Switzerland) means that nano-titanium dioxide today reaches an average concentration of 61 micrograms per kilo in affected soils.

Knowing the degree of accumulation in the environment is only the first step in the risk assessment of nanomaterials, however. Now this data has to be compared with results of eco-toxicological tests and the statutory thresholds, says Nowack. A risk assessment has not been carried out with his new model so far. Earlier work with data from a static model showed, however, that the concentrations determined for all four nanomaterials investigated are not expected to have any impact on the environment.

But in the case of nanozinc at least, its concentration in the environment is approaching the critical level. This is why this particular nanomaterial has to be given priority in future eco-toxicological studies – even though nanozinc is produced in smaller quantities than nano-titanium dioxide. Furthermore, eco-toxicological tests have until now been carried out primarily with freshwater organisms. The researchers conclude that additional investigations using soil-dwelling organisms are a priority.

Here are links to and citations for papers featuring the work,

Dynamic Probabilistic Modeling of Environmental Emissions of Engineered Nanomaterials by Tian Yin Sun†, Nikolaus A. Bornhöft, Konrad Hungerbühler, and Bernd Nowack. Environ. Sci. Technol., 2016, 50 (9), pp 4701–4711 DOI: 10.1021/acs.est.5b05828 Publication Date (Web): April 04, 2016

Copyright © 2016 American Chemical Society

Probabilistic environmental risk assessment of five nanomaterials (nano-TiO2, nano-Ag, nano-ZnO, CNT, and fullerenes) by Claudia Coll, Dominic Notter, Fadri Gottschalk, Tianyin Sun, Claudia Som, & Bernd Nowack. Nanotoxicology Volume 10, Issue 4, 2016 pages 436-444 DOI: 10.3109/17435390.2015.1073812 Published online: 10 Nov 2015

The first paper, which is listed in Environmental Science & Technology, appears to be open access while the second paper is behind a paywall.

Identifying minute amounts of nanomaterial in environmental samples

It’s been a while since I’ve had a story from one of Germany’s Franhaufer Institutes. Their stories are usually focused on research that’s about to commercialized but that’s not the case this time according to an April 28, 2016 news item on Nanowerk,

It is still unclear what the impact is on humans, animals and plants of synthetic nanomaterials released into the environment or used in products. It’s very difficult to detect these nanomaterials in the environment since the concentrations are so low and the particles so small. Now the partners in the NanoUmwelt project have developed a method that is capable of identifying even minute amounts of nanomaterials in environmental samples.

An April 28, 2016 Fraunhofer Institute press release, which originated the news item, provides more detail about the technology and about the NanoUmwelt project along with a touch of whimsy,

Tiny dwarves keep our mattresses clean, repair damage to our teeth, stop eggs sticking to our pans, and extend the shelf life of our food. We are talking about nanomaterials – “nano” comes from the Greek word for “dwarf”. These particles are just a few billionths of a meter small, and they are used in a wide range of consumer products. However, up to now the impact of these materials on the environment has been largely unknown, and information is lacking on the concentrations and forms in which they are present there. “It’s true that many laboratory studies have examined the effect of nanomaterials on human and animal cells. To date, though, it hasn’t been possible to detect very small amounts in environmental samples,” says Dr. Yvonne Kohl from the Fraunhofer Institute for Biomedical Engineering IBMT in Sulzbach.

A millionth of a milligram per liter 

That is precisely the objective of the NanoUmwelt project. The interdisciplinary project team is made up of eco- and human toxicologists, physicists, chemists and biologists, and they have just managed to take their first major step forward in achieving their goal: they have developed a method for testing a variety of environmental samples such as river water, animal tissue, or human urine and blood that can detect nanomaterials at a concentration level of nanogram per liter (ppb – parts per billion). That is equivalent to half a sugar cube in the volume of water contained in 1,000 competition swimming pools. Using the new method, it is now possible to detect not just large amounts of nanomaterials in clear fluids, as was previously the case, but also very few particles in complex substance mixtures such as human blood or soil samples. The approach is based on field-flow fractionation (FFF), which can be used to separate complex heterogeneous mixtures of fluids and particles into their component parts – while simultaneously sorting the key components by size. This is achieved by the combination of a controlled flow of fluid and a physical separation field, which acts perpendicularly on the flowing suspension.

For the detection process to work, environmental samples have to be appropriately processed. The team from Fraunhofer IBMT’s Bioprocessing & Bioanalytics Department prepared river water, human urine, and fish tissue to be fit for the FFF device. “We prepare the samples with special enzymes. In this process, we have to make sure that the nanomaterials are not destroyed or changed. This allows us to detect the real amounts and forms of the nanomaterials in the environment,” explains Kohl. The scientists have special expertise when it comes to providing, processing and storing human tissue samples. Fraunhofer IBMT has been running the “German Environmental Specimen Bank (ESB) – Human Samples”since January 2012 on behalf of Germany’s Environment Agency (UBA). Each year the research institute collects blood and urine samples from 120 volunteers in four cities in Germany. Individual samples are a valuable tool for mapping the trends over time of human exposure to pollutants. ”In addition, blood and urine samples have been donated for the NanoUmwelt project and put into cryostorage at Fraunhofer IBMT. We used these samples to develop our new detection method,” says Dr. Dominik Lermen, manager of the working group on Biomonitoring & Cryobanks at Fraunhofer IBMT. After approval by the UBA, some of the human samples in the ESB archive may also be examined using the new method.

Developing new cell culture models

Nanomaterials end up in the environment via different pathways, inter alia the sewage system. Human beings and animals presumably absorb them through biological barriers such as the lung or intestine. The project team is simulating these processes in petri dishes in order to understand how nanomaterials are transported across these barriers. “It’s a very complex process involving an extremely wide range of cells and layers of tissue,” explains Kohl. The researchers replicate the processes in a way as realistic as possible. They do this by, for instance, measuring the electrical flows within the barriers to determine the functionality of these barriers – or by simulating lung-air interaction using clouds of artificial fog. In the first phase of the NanoUmwelt project, the IBMT team succeeded in developing several cell culture models for the transport of nanomaterials across biological barriers. IBMT worked together with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME, which used pluripotent stem cells to develop a model for investigating cardiotoxicity. Empa, the Swiss partner in the project, delivered a placental barrier model for studying the transport of nanomaterials between mother and child.

Next, the partners want to use their method to measure the concentrations of nanoparticles in a wide variety of environmental samples. They will then analyze the results obtained so as to be in a better position to assess the behavior of nanomaterials in the environment and their potential danger for humans, animals, and the environment. “Our next goal is to detect particles in even smaller quantities,” says Kohl. To achieve this, the scientists are planning to use special filters to remove distracting elements from the environmental samples, and they are looking forward to develop new processing techniques.
NanoUmwelt – the objective

The NanoUmwelt research project was launched in October 2014 and will last for 36 months. Its objective is to develop methods for detecting minute amounts of nanomaterials in environmental samples. Using this information, the project partners will assess the effect of nanomaterials on humans, animals, and the environment. They are focusing on commercially significant, slowly degradable, metallic (silver, titanium dioxide), carbonic (carbon nanotubes) and polymer-based (polystyrene) nanomaterials.

http://www.nanopartikel.info/projekte/laufende-projekte/nanoumwelt

NanoUmwelt – the partners

The German Federal Ministry for Education and Research (BMBF) is providing the NanoUmwelt project with 1.8 million euros of funding as part of its NanoCare program. Led by Postnova Analytics GmbH, ten further partners are collaborating together on the project. Besides the Fraunhofer Institutes for Biomedical Engineering IBMT and for Molecular Biology and Applied Ecology IME, these partners include Germany’s Environment Agency, Empa (the Swiss Federal Laboratories for Materials Science and Technology), PlasmaChem GmbH, Senova GmbH (biological sciences and engineering), fzmb GmbH (Research Centre of Medical Technology and Biotechnology), the universities of Trier and Frankfurt, and the Rhine Water Control Station in Worms.

http://www.nanopartikel.info/projekte/laufende-projekte/nanoumwelt

How small is nano?

A nanometer (nm) is a billionth of a meter. To put this into context: the size of a single nanoparticle relative to a football is the same as that of a football relative to the earth. In the main, nanoscopic particles are not new materials. It’s simply that the increased overall surface area of these tiny particles gives them new functionalities as against larger particles of the same material.


The German Environmental Specimen Bank  

The German Environmental Specimen Bank (ESB) provides the country’s Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB) with a scientific basis both for adopting appropriate measures concerning environment and nature conservation and for monitoring the success of those measures. The human samples collected by the Fraunhofer Institute for Biomedical Engineering IBMT on behalf of Germany’s Environment Agency (UBA) give an overview of human exposure to environmental pollutants.

https://www.umweltprobenbank.de/de

Assuming I’ve understood this correctly, the NanoUmwelt project will be ending in 2017 (36 months in total) and the researchers have expended 1/2 of the time (18 months) allotted to developing a technique for measuring nanomaterials of heretofore unheard of quantities in environmental samples. With that done, researchers are now going to use the technique with human samples over the next 18 months.

Carrot-based helmets: a nanocellulose commercialization story

NanoCelluComp, a European Commission-funded project, whose name bears a close resemblance to a Scottish company, CelluComp, ended last year (my March 5, 2014 post). Both, NanoCelluComp and CelluComp, were/are involved in research featuring carrots and nanocellulose.

An Aug. 6, 2015 news item on ScienceDaily describes some Swiss/Scottish research into using carrot nanofibers in helmets,

Crackpot idea or recipe for success? This is a question entrepreneurs often face. Is it worth converting the production process to a new, ecologically better material? Empa [Swiss Federal Laboratories for Materials Science and Technology or Eidgenössische Materialprüfungs- und Forschungsansta] has developed an analysis method that enables companies to simulate possible scenarios — and therefore avoid bad investments. Here’s an example: Nanofibers made of carrot waste from the production of carrot juice, which can be used to reinforce synthetic parts.

All over the world, research is being conducted into biodegradable and recyclable synthetics. However, fiber-reinforced components remain problematic — if glass or carbon fibers are used. Within the scope of an EU research project, the Scottish company Cellucomp Limited has now developed a method to obtain nanofibers from carrot waste. [emphasis mine] These fibers would be both cost-effective and biodegradable. However, is the method, which works in the lab, also marketable on a large scale?

Here’s a composite image illustrating the notion of a carrot-based helmet,

Motorcycle helmets consist of fiber-reinforced synthetic material. Instead of glass fibers, a biological alternative is now also possible: plant fibers from the production of carrot juice. Empa researchers are now able to analyze whether this kind of production makes sense from an ecological and economical perspective – before money is actually invested in production plants.  Photo: 4ever.eu, composite photo: Empa

Motorcycle helmets consist of fiber-reinforced synthetic material. Instead of glass fibers, a biological alternative is now also possible: plant fibers from the production of carrot juice. Empa researchers are now able to analyze whether this kind of production makes sense from an ecological and economical perspective – before money is actually invested in production plants.
Photo: 4ever.eu, composite photo: Empa

An Aug. 6, 2015 Empa press release (also on EurekAlert), which originated the news item, provides more details abut the drive to commercialize this nanocellulose product,

An MPAS (multi-perspective application selection) method developed at Empa helps identify the industrial sectors where new materials might be useful from a technical and economical perspective. At the same time, MPAS also considers the ecological aspect of these new materials. The result for our example: Nanofibers made of carrot waste might be used in the production of motorcycle helmets or side walls for motorhomes in the future.

Three-step analysis

In order to clarify a new material’s market potential, Empa researchers Fabiano Piccinno, Roland Hischier and Claudia Som proceed in three steps for the MPAS method. First of all, the field of possible applications is defined: Which applications come into question based on the technical properties and what categories can they be divided into? Can the new material replace an existing one?

The second step concerns the technical feasibility and market potential: Can the material properties required be achieved with the technical process? Might the product quality vary from one production batch to the next? Can the lab process be upgraded to an industrial scale cost-effectively? Is the material more suited to the low-cost sector or expensive luxury goods? And finally: Does the product meet the legal standards and the customers’ certification needs?

In the third step, the ecological aspect is eventually examined: Is this new material for the products identified really more environmentally friendly – once all the steps from product creation to recycling have been factored in? Which factors particularly need to be considered during production stage to manufacture the material in as environmentally friendly a way as possible?

Industrial production on a five-ton scale – calculated theoretically

The MPAS approach enables individual scenarios for a future production to be calculated with an extremely high degree of accuracy. In the case of the carrot waste nanofibers, for instance, it is crucial whether five tons of fresh carrots or only 209 kilograms of carrot waste (fiber waste from the juicing process) are used as the base material for their production. The issue of whether the solvent is ultimately recycled or burned affects the production costs. And the energy balance depends on how the enzymes that loosen the fibers from the carrots are deactivated. In the lab, this takes place via heat; for production on an industrial level, the use of bleaching agents would be more cost-effective.

Conclusion: six possible applications for “carrot fibers“

For fiber production from carrot waste, the MPAS analysis identified six possible customer segments for the Scottish manufacturer Cellucomp that are worth taking a closer look at: Protective equipment and devices for recreational sport, special vehicles, furniture, luxury consumer goods and industrial manufacturing. The researchers listed the following examples: Motorcycle helmets and surfboards, side walls for motorhomes, dining tables, high-end loudspeaker boxes and product protection mats for marble-working businesses. Similarly detailed analyses can also be conducted for other renewable materials – before a lot of money is actually invested in production plants.

There are other attempts to commercialize nanocellulose (as I understand it, cellulose is one of the most common materials on earth and can be derived from several sources including trees, bananas, pineapples, and more) mentioned in my July 30, 2015 post. I will repeat a question from that post, where are the Canadian research efforts to develop and commercialize nanocellulose? If you have information, please do let me know.

Nanosafety research: a quality control issue

Toxicologist Dr. Harald Krug has published a review of several thousand studies on nanomaterials safety exposing problematic research methodologies and conclusions. From an Oct. 29, 2014 news item on Nanowerk (Note: A link has been removed),

Empa [Swiss Federal Laboratories for Materials Science and Technology] toxicologist Harald Krug has lambasted his colleagues in the journal Angewandte Chemie (“Nanosafety Research—Are We on the Right Track?”). He evaluated several thousand studies on the risks associated with nanoparticles and discovered no end of shortcomings: poorly prepared experiments and results that don’t carry any clout. Instead of merely leveling criticism, however, Empa is also developing new standards for such experiments within an international network.

An Oct. 29, 2014 Empa press release (also on EurekAlert), which originated the news item, describes the new enthusiasm for research into nanomaterials and safety,

Researching the safety of nanoparticles is all the rage. Thousands of scientists worldwide are conducting research on the topic, examining the question of whether titanium dioxide nanoparticles from sun creams can get through the skin and into the body, whether carbon nanotubes from electronic products are as hazardous for the lungs as asbestos used to be or whether nanoparticles in food can get into the blood via the intestinal flora, for instance. Public interest is great, research funds are flowing – and the number of scientific projects is skyrocketing: between 1980 and 2010, a total of 5,000 projects were published, followed by another 5,000 in just the last three years. However, the amount of new knowledge has only increased marginally. After all, according to Krug the majority of the projects are poorly executed and all but useless for risk assessments.

The press release goes on to describe various pathways into the body and problems with research methodologies,

How do nanoparticles get into the body?

Artificial nanoparticles measuring between one and 100 nanometers in size can theoretically enter the body in three ways: through the skin, via the lungs and via the digestive tract. Almost every study concludes that healthy, undamaged skin is an effective protective barrier against nanoparticles. When it comes to the route through the stomach and gut, however, the research community is at odds. But upon closer inspection the value of many alarmist reports is dubious – such as when nanoparticles made of soluble substances like zinc oxide or silver are being studied. Although the particles disintegrate and the ions drifting into the body are cytotoxic, this effect has nothing to do with the topic of nanoparticles but is merely linked to the toxicity of the (dissolved) substance and the ingested dose.

Laboratory animals die in vain – drastic overdoses and other errors

Krug also discovered that some researchers maltreat their laboratory animals with absurdly high amounts of nanoparticles. Chinese scientists, for instance, fed mice five grams of titanium oxide per kilogram of body weight, without detecting any effects. By way of comparison: half the amount of kitchen salt would already have killed the animals. A sloppy job is also being made of things in the study of lung exposure to nanoparticles: inhalation experiments are expensive and complex because a defined number of particles has to be swirled around in the air. Although it is easier to place the particles directly in the animal’s windpipe (“instillation”), some researchers overdo it to such an extent that the animals suffocate on the sheer mass of nanoparticles.

While others might well make do without animal testing and conduct in vitro experiments on cells, here, too, cell cultures are covered by layers of nanoparticles that are 500 nanometers thick, causing them to die from a lack of nutrients and oxygen alone – not from a real nano-effect. And even the most meticulous experiment is worthless if the particles used have not been characterized rigorously beforehand. Some researchers simply skip this preparatory work and use the particles “straight out of the box”. Such experiments are irreproducible, warns Krug.

As noted in the news item, the scientists at Empa have devised a solution to some to of the problems (from the press release),

The solution: inter-laboratory tests with standard materials
Empa is thus collaborating with research groups like EPFL’s Powder Technology Laboratory, with industrial partners and with Switzerland’s Federal Office of Public Health (FOPH) to find a solution to the problem: on 9 October the “NanoScreen” programme, one of the “CCMX Materials Challenges”, got underway, which is expected to yield a set of pre-validated methods for lab experiments over the next few years. It involves using test materials that have a closely defined particle size distribution, possess well-documented biological and chemical properties and can be altered in certain parameters – such as surface charge. “Thanks to these methods and test substances, international labs will be able to compare, verify and, if need be, improve their experiments,” explains Peter Wick, Head of Empa’s laboratory for Materials-Biology Interactions.

Instead of the all-too-familiar “fumbling around in the dark”, this would provide an opportunity for internationally coordinated research strategies to not only clarify the potential risks of new nanoparticles in retrospect but even be able to predict them. The Swiss scientists therefore coordinate their research activities with the National Institute of Standards and Technology (NIST) in the US, the European Commission’s Joint Research Center (JRC) and the Korean Institute of Standards and Science (KRISS).

Bravo! and thank you Dr. Krug and Empa for confirming something I’ve suspected due to hints from more informed commentators. Unfortunately my ignorance. about research protocols has not permitted me to undertake a better analysis of the research. ,

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

Nanosafety Research—Are We on the Right Track? by Prof. Dr. Harald F. Krug. Angewandte Chemie International Edition DOI: 10.1002/anie.201403367 Article first published online: 10 OCT 2014

This is an open access paper.

Fewer silver nanoparticles washed off coated textiles

This time I have two complementary tidbits about silver nanoparticles, their use in textiles, and washing. The first is a June 30, 2014 news item on Nanowerk, with the latest research from Empa (Swiss Federal Laboratories for Materials Science and Technology) on silver nanoparticles being sloughed off textiles when washing them,

The antibacterial properties of silver-coated textiles are popular in the fields of sport and medicine. A team at Empa has now investigated how different silver coatings behave in the washing machine, and they have discovered something important: textiles with nano-coatings release fewer nanoparticles into the washing water than those with normal coatings …

A June 30,  2014 Empa news release, which originated the news item, describes the findings in more detail,

If it contains ‘nano’, it doesn’t primarily leak ‘nano’: at least that’s true for silver-coated textiles, explains Bernd Nowack of the «Technology and Society» division at Empa. During each wash cycle a certain amount of the silver coating is washed out of the textiles and ends up in the waste water. [emphasis mine] Empa analysed this water; it turned out that nano-coated textiles release hardly any nano-particles. That’s quite the opposite to ordinary coatings, where a lot of different silver particles were found. Moreover, nano-coated silver textiles generally lose less silver during washing. This is because considerably less silver is incorporated into textile fabrics with nano-coating, and so it is released in smaller quantities for the antibacterial effect than is the case with ordinary coatings. A surprising result that has a transformative effect on future analyses and on the treatment of silver textiles. «All silver textiles behave in a similar manner – regardless of whether they are nano-coated or conventionally-coated,» says Nowack. This is why nano-textiles should not be subjected to stricter regulation than textiles with conventional silver-coatings, and this is relevant for current discussions concerning possible special regulations for nano-silver.

But what is the significance of silver particles in waste water? Exposed silver reacts with the (small quantities of) sulphur in the air to form silver sulphide, and the same process takes place in the waste water treatment plant. The silver sulphide, which is insoluble, settles at the bottom of the sedimentation tank and is subsequently incinerated with the sewage sludge. So hardly any of the silver from the waste water remains in the environment. Silver is harmless because it is relatively non-toxic for humans. Even if silver particles are released from the textile fabric as a result of strong sweating, they are not absorbed by healthy skin.

I’ve highlighted Nowack’s name as he seems to have changed his opinions since I first wrote about his work with silver nanoparticles in textiles and washing in a Sept. 8, 2010 posting,

“We found that the total released varied considerably from less than 1 to 45 percent of the total nanosilver in the fabric and that most came out during the first wash,” Bernd Nowack, head of the Environmental Risk Assessment and Management Group at the Empa-Swiss Federal Laboratories for Materials Testing and Research, tells Nanowerk. “These results have important implications for the risk assessment of silver textiles and also for environmental fate studies of nanosilver, because they show that under certain conditions relevant to washing, primarily coarse silver-containing particles are released.”

How did the quantity of silver nanoparticles lost in water during washing change from “less than 1 to 45 percent of the total nanosilver in the fabric” in a 2010 study to “Empa analysed this water; it turned out that nano-coated textiles release hardly any nano-particles” in a 2014 study? It would be nice to find out if there was a change in the manufacturing process and whether or not this is global change or one undertaken in Switzerland alone.

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

Presence of Nanoparticles in Wash Water from Conventional Silver and Nano-silver Textiles by Denise M. Mitrano, Elisa Rimmele, Adrian Wichser, Rolf Erni, Murray Height, and Bernd Nowack. ACS Nano, Article ASAP DOI: 10.1021/nn502228w Publication Date (Web): June 18, 2014

Copyright © 2014 American Chemical Society

This paper is behind a paywall.

The second tidbit is from Iran and may help to answer my questions about the Empa research. According to a July 7, 2014 news item on Nanowerk (Note: A link has been removed),

Writing in The Journal of The Textile Institute (“Effect of silver nanoparticles morphologies on antimicrobial properties of cotton fabrics”), researchers from Islamic Azad University in Iran, describe the best arrangement for increasing the antibacterial properties of textile products by studying various structures of silver nanoparticles.

A July 7, 2014 news release from the Iran Nanotechnology Initiative Council (INIC), which originated the news item, provides more details,

By employing the structure presented by the researchers, the amount of nanoparticles stabilization on the fabric and the durability of its antibacterial properties increase after washing and some problems are solved, including the change in the fabric color.

Using the results of this research creates diversity in the application of various structures of nanoparticles in the complementary process of cotton products. Moreover, the color of the fabric does not change as the amount of consumed materials decreases, because the excess use of silver was the cause of this problem. On the other hand, the stability and durability of nanoparticles increase against standard washing. All these facts result in the reduction in production cost and increase the satisfaction of the customers.

The researchers have claimed that in comparison with other structures, hierarchical structure has much better antibacterial activity (more than 91%) even after five sets of standard washing.

This work on morphology would seem to answer my question about the big difference in Nowack’s description of the quantity of silver nanoparticles lost due to washing. I am assuming, of course, that something has changed with regard to the structure and/or shape of the silver nanoparticles coating the textiles used in the Empa research.

Getting back to the work in Iran, here’s a link to and a citation for the paper,

Effect of silver nanoparticles morphologies on antimicrobial properties of cotton fabrics by Mohammad Reza Nateghia & Hamed Hajimirzababa. The Journal of The Textile Institute Volume 105, Issue 8, 2014 pages 806-813 DOI: 10.1080/00405000.2013.855377 Published online: 21 Jan 2014

This paper is behind a paywall.

Indestructible spinal disc implants?

This June 2, 2014 news item on Nanowerk is a bit confusing but despite all the talk about hips and knees the research described is largely concerned with spinal disc implants,

Artificial joints have a limited lifespan. After a few years, many hip and knee joints have to be replaced. Much more complex are intervertebral disc implants, which cannot easily be replaced after their “expiry date” and which up to now have had to be reinforced in most cases. This restricts the patient’s freedom of movement considerably. Researchers at Empa have now succeeded in coating mobile intervertebral disc implants so that they show no wear and will now last for a lifetime.

The May 28, 2014 Empa (Swiss Federal Laboratories for Materials Science and Technology) news release, which originated the news item, provides more details,

Due to the daily stresses and movement in the body, even the best artificial joints wear out; the material undergoes wear, and wear particles can trigger unwanted immune reactions, making it necessary to replace the joint. This is normally a standard procedure that can be repeated up to three times with most implants.  As bone material is lost each time an implant is explanted, the new joint has to replace more bone and is therefore larger. In the case of intervertebral discs, this is virtually impossible. They are too close to spinal nerves and tissue structures that could be damaged by another operation.

Up to now, intervertebral discs have not been replaced by mobile joints, but by so-called cages, a kind of place holder that both supports and allows the adjacent vertebrae to grow and fuse together. However, this causes stiffening at the point where previously the disc had provided adequate freedom of movement.  Over the years, this stiffening can result in the adjacent discs also having to be reinforced due to the increased stress on them. Mobile intervertebral disc implants could reduce this problem. However, many products currently available carry the risk of triggering allergies or rejection reactions due to material abrasion.

Initial attempts to increase the lifespan of artificial joints were made by various manufacturers in the past using a super-hard coating made of DLC (“diamond-like carbon”) – with disastrous consequences. Approximately 80% of DLC-coated hip joints failed within just eight years. Researchers at Empa’s “Laboratory for Nanoscale Materials Science” investigated this problem and found that the implant failure did not originate from the coating itself, but was caused by the corrosion behaviour of the bonding agent between the DLC layer and the metal body. This layer was made of silicon which corroded over the years, causing it to flake, which led to increased abrasion and, as a result, bone loss. “Our aim was to find a bonding agent which does not corrode and which lasts a lifetime in the body,” explains Kerstin Thorwarth.

This was a laborious task, as the Empa researcher emphasises: “We tried half the periodic table.”  One was finally found and tantalum was used as the bonding agent.  This coating was tested in a so-called total disc replacement – a mobile disc implant. We simulated 100 million cycles, i.e. about 100 years of movement in a specially designed joint simulator.  The small intervertebral disc implant held out, remaining fully operational with no abrasion or corrosion. The new bonding agent is soon also to be used in combination with DLC coatings for other joints. “The intervertebral disc is the most awkward joint in terms of implants. Because tantalum has performed so well, the DLC project can now be applied to other joints,” says Thorwarth.

If I understand the research rightly, proving that this technology does not wear out by testing it on the most difficult of the ‘joints’ to implant, an intervertebral disc, ensures success for ‘easier’ joints such as hips and knees.

I believe my most recent post about joint replacements is this Feb. 5, 2013 post which briefly mentions contrasting research approaches from Case Western University and MIT (Massachusetts Institute of Technology) while noting that people with joint replacements could be considered cyborgs.

Mopping up that oil spill with a nanocellulose sponge and a segue into Canadian oil and politics

Empa (Swiss Federal Laboratories for Materials Science and Technology or ,in German, Eidgenössische Materialprüfungs- und Forschungsanstalt) has announced the development of a nanocellulose sponge useful for cleaning up oil spills in a May 5, 2014 news item on Nanowerk (Note: A link has been removed),

A new, absorbable material from Empa wood research could be of assistance in future oil spill accidents: a chemically modified nanocellulose sponge. The light material absorbs the oil spill, remains floating on the surface and can then be recovered. The absorbent can be produced in an environmentally-friendly manner from recycled paper, wood or agricultural by-products (“Ultralightweight and Flexible Silylated Nanocellulose Sponges for the Selective Removal of Oil from Water”).

A May 2, 2014 Empa news release (also on EurekAlert*}, which originated the news item, includes a description of the potential for oil spills due to transport issues, Empa’s proposed clean-up technology, and a request for investment,

All industrial nations need large volumes of oil which is normally delivered by ocean-going tankers or via inland waterways to its destination. The most environmentally-friendly way of cleaning up nature after an oil spill accident is to absorb and recover the floating film of oil. The Empa researchers Tanja Zimmermann and Philippe Tingaut, in collaboration with Gilles Sèbe from the University of Bordeaux, have now succeeded in developing a highly absorbent material which separates the oil film from the water and can then be easily recovered, “silylated” nanocellulose sponge. In laboratory tests the sponges absorbed up to 50 times their own weight of mineral oil or engine oil. They kept their shape to such an extent that they could be removed with pincers from the water. The next step is to fine tune the sponges so that they can be used not only on a laboratory scale but also in real disasters. To this end, a partner from industry is currently seeked.

Here’s what the nanocellulose sponge looks like (oil was dyed red and the sponge has absorbed it from the water),

The sponge remains afloat and can be pulled out easily. The oil phase is selectively removed from the surface of water. Image: Empa

The sponge remains afloat and can be pulled out easily. The oil phase is selectively removed from the surface of water.
Image: Empa

The news release describes the substance, nanofibrillated cellulose (NFC), and its advantages,

Nanofibrillated Cellulose (NFC), the basic material for the sponges, is extracted from cellulose-containing materials like wood pulp, agricultural by products (such as straw) or waste materials (such as recycled paper) by adding water to them and pressing the aqueous pulp through several narrow nozzles at high pressure. This produces a suspension with gel-like properties containing long and interconnected cellulose nanofibres .

When the water from the gel is replaced with air by freeze-drying, a nanocellulose sponge is formed which absorbs both water and oil. This pristine material sinks in water and is thus not useful for the envisaged purpose. The Empa researchers have succeeded in modifying the chemical properties of the nanocellulose in just one process step by admixing a reactive alkoxysilane molecule in the gel before freeze-drying. The nanocellulose sponge loses its hydrophilic properties, is no longer suffused with water and only binds with oily substances.

In the laboratory the “silylated” nanocellulose sponge absorbed test substances like engine oil, silicone oil, ethanol, acetone or chloroform within seconds. Nanofibrillated cellulose sponge, therefore, reconciles several desirable properties: it is absorbent, floats reliably on water even when fully saturated and is biodegradable.

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

Ultralightweight and Flexible Silylated Nanocellulose Sponges for the Selective Removal of Oil from Water by Zheng Zhang, Gilles Sèbe, Daniel Rentsch, Tanja Zimmermann, and Philippe Tingaut. Chem. Mater., 2014, 26 (8), pp 2659–2668 DOI: 10.1021/cm5004164 Publication Date (Web): April 10, 2014

Copyright © 2014 American Chemical Society

This article is behind a paywall.

I featured ‘nanocellulose and oil spills’ research at the University Wisconsin-Madison in a Feb. 26, 2014 post titled, Cleaning up oil* spills with cellulose nanofibril aerogels (Note: I corrected a typo in my headline hence the asterisk). I also have a Dec. 31, 2013 piece about a nanotechnology-enabled oil spill recovery technology project (Naimor) searching for funds via crowdfunding. Some major oil projects being considered in Canada and the lack of research on remediation are also mentioned in the post.

Segue Alert! As for the latest on Canada and its oil export situation, there’s a rather interesting May 2, 2014 Bloomberg.com article Canada Finds China Option No Easy Answer to Keystone Snub‘ by Edward Greenspon, Andrew Mayeda, Jeremy van Loon and Rebecca Penty describing two Canadian oil projects and offering a US perspective,

It was February 2012, three months since President Barack Obama had phoned the Canadian prime minister to say the Keystone XL pipeline designed to carry vast volumes of Canadian crude to American markets would be delayed.

Now Harper [Canadian Prime Minister Stephen Harper] found himself thousands of miles from Canada on the banks of the Pearl River promoting Plan B: a pipeline from Alberta’s landlocked oil sands to the Pacific Coast where it could be shipped in tankers to a place that would certainly have it — China. It was a country to which he had never warmed yet that served his current purposes. [China’s President at that time was Hu Jintao, 2002 – 2012; currently the President is Xi Jinping, 2013 – ]

The writers do a good job of describing a number of factors having an impact on one or both of the pipeline projects. However, no mention is made in the article that Harper is from the province of Alberta and represents that province’s Calgary Southwest riding. For those unfamiliar with Calgary, it is a city dominated by oil companies. I imagine Mr. Harper is under considerable pressure to resolve oil export and transport issues and I would expect they would prefer to resolve the US issues since many of those oil companies in Calgary have US headquarters.

Still, it seems simple, if the US is not interested as per the problems with the Keystone XL pipeline project, ship the oil to China via a pipeline through the province of British Columbia and onto a tanker. What the writers do not mention is yet another complicating factor, Trudeau, both Justin and, the deceased, Pierre.

As Prime Minister of Canada, Pierre Trudeau was unloved in Alberta, Harper’s home province, due to his energy policies and the formation of the National Energy Board. Harper appears, despite his denials, to have an antipathy towards Pierre Trudeau that goes beyond the political to the personal and it seems to extend beyond Pierre’s grave to his son, Justin. A March 21, 2014 article by Mark Kennedy for the National Post describes Harper’s response to Trudeau’s 2000 funeral this way,

Stephen Harper, then the 41-year-old president of the National Citizens Coalition (NCC), was a proud conservative who had spent three years as a Reform MP. He had entered politics in the mid-1980s, in part because of his disdain for how Pierre Trudeau’s “Just Society” had changed Canada.

So while others were celebrating Trudeau’s legacy, Harper hammered out a newspaper article eviscerating the former prime minister on everything from policy to personality.

Harper blasted Trudeau Sr. for creating “huge deficits, a mammoth national debt, high taxes, bloated bureaucracy, rising unemployment, record inflation, curtailed trade and declining competitiveness.”

On national unity, he wrote that Trudeau was a failure. “Only a bastardized version of his unity vision remains and his other policies have been rejected and repealed by even his own Liberal party.”

Trudeau had merely “embraced the fashionable causes of his time,” wrote Harper.

Getting personal, he took a jab at Trudeau over not joining the military during the Second World War: “He was also a member of the ‘greatest generation,’ the one that defeated the Nazis in war and resolutely stood down the Soviets in the decades that followed. In those battles however, the ones that truly defined his century, Mr. Trudeau took a pass.”

The article was published in the National Post Oct. 5, 2000 — two days after the funeral.

Kennedy’s article was occasioned by the campaign being led by Harper’;s Conservative party against the  leader (as of April 2013) of the Liberal Party, Justin Trudeau.

It’s hard to believe that Harper’s hesitation over China is solely due to human rights issues especially  since Harper has not been noted for consistent interest in those issues and, more particularly, since Prime Minister Pierre Trudeau was one of the first ‘Western’ leaders to visit communist China . Interestingly, Harper has been much more enthusiastic about the US than Pierre Trudeau who while addressing the Press Club in Washington, DC in March 1969, made this observation (from the Pierre Trudeau Wikiquote entry),

Living next to you [the US] is in some ways like sleeping with an elephant. No matter how friendly and even-tempered is the beast, if I can call it that, one is affected by every twitch and grunt.

On that note, I think Canada is always going to be sleeping with an elephant; the only question is, who’s the elephant now? In any event, perhaps Harper is more comfortable with the elephant he knows and that may explain why China’s offer to negotiate a free trade agreement has been left unanswered (this too was not noted in the Bloomberg article). The offer and lack of response were mentioned by Yuen Pau Woo, President and CEO of the Asia Pacific Foundation of Canada, who spoke at length about China, Canada, and their trade relations at a Jan. 31, 2014 MP breakfast (scroll down for video highlights of the Jan. 31, 2014 breakfast) held by Member of Parliament (MP) for Vancouver-Quadra, Joyce Murray.

Geopolitical tensions and Canadian sensitivities aside, I think Canadians in British Columbia (BC), at least, had best prepare for more oil being transported and the likelihood of spills. In fact, there are already more shipments according to a May 6, 2014 article by Larry Pynn for the Vancouver Sun,

B.C. municipalities work to prevent a disastrous accident as rail transport of oil skyrockets

The number of rail cars transporting crude oil and petroleum products through B.C. jumped almost 200 per cent last year, reinforcing the resolve of municipalities to prevent a disastrous accident similar to the derailment in Lac-Mégantic in Quebec last July [2013].

Transport Canada figures provided at The Vancouver Sun’s request show just under 3,400 oil and petroleum rail-car shipments in B.C. last year, compared with about 1,200 in 2012 and 50 in 2011.

The figures come a week after The Sun revealed that train derailments jumped 20 per cent to 110 incidents last year in B.C., the highest level in five years.

Between 2011 and 2012, there was an increase of 2400% (from 50 to 1200) of oil and petroleum rail-car shipments in BC. The almost 300% increase in shipments between 2012 and 2013 seems paltry in comparison.  Given the increase in shipments and the rise in the percentage of derailments, one assumes there’s an oil spill waiting to happen. Especially so, if the Canadian government manages to come to an agreement regarding the proposed pipeline for BC and frankly, I have concerns about the other pipeline too, since either will require more rail cars, trucks, and/or tankers for transport to major centres edging us all closer to a major oil spill.

All of this brings me back to Empa, its oil-absorbing nanocellulose sponges, and the researchers’ plea for investors and funds to further their research. I hope they and all the other researchers (e.g., Naimor) searching for ways to develop and bring their clean-up ideas to market find some support.

*EurekAlert link added May 7, 2014.

ETA May 8, 2014:  Some types of crude oil are more flammable than others according to a May 7, 2014 article by Lindsay Abrams for Salon.com (Note: Links have been removed),

Why oil-by-rail is an explosive disaster waiting to happen
A recent spate of fiery train accidents all have one thing in common: highly volatile cargo from North Dakota

In case the near continuous reports of fiery, deadly oil train accidents hasn’t been enough to convince you, Earth Island Journal is out with a startling investigative piece on North Dakota’s oil boom and the dire need for regulations governing that oil’s transport by rail.

The article is pegged to the train that derailed and exploded last summer in  [Lac-Mégantic] Quebec, killing 47 people, although it just as well could have been the story of the train that derailed and exploded in Alabama last November, the train that derailed and exploded in North Dakota last December, the train that derailed and exploded in Virginia last week or — let’s face it — any future accidents that many see as an inevitability.

The Bakken oil fields in North Dakota are producing over a million barrels of crude oil a day, more than 60 percent of which is shipped by rail. All that greenhouse gas-emitting fossil fuel is bad enough; that more oil spilled in rail accidents last year than the past 35 years combined is also no small thing. But the particular chemical composition of Bakken oil lends an extra weight to these concerns: according to the Pipeline and Hazardous Materials Safety Administration, it may be more flammable and explosive than traditional crude.

While Abrams’ piece is not focused on oil cleanups, it does raise some interesting questions about crude oil transport and whether or not the oil from Alberta might also be more than usually dangerous.