Scanning electron microscope image of a bioactive glass scaffold seeded with human osteoblasts (MG-63). The seeded cells are distributed over the whole scaffold area and well adhered on the surface. This image shows that bone cells can grow on and through this bioactive glass construct. Credit: Boccaccini; Uni-Erlangen.

Following last year’s successful Pacific Rim Engineering Ceramics Summit, The ACerS Engineering Ceramics Division has organized a transatlantic European Union-USA Ceramics Summit for the upcoming 36th International Conference on Advanced Ceramics and Composites (36th ICACC), Jan. 22-27, 2012 in Daytona Beach, Florida.

According to organizers of the summit, there has been major progress in the R&D and commercialization of engineered ceramics over the last 50 years in Europe and the US. Seminal contributions have led to the engineering of ceramics with multifunctional properties and broad applications in energy, aerospace, healthcare, communication, infrastructure, transportation, environmental, and other industries. As a result, the living standards and quality of life have been raised for people worldwide.

The goal of the EU-USA Summit is to provide a forum for the information exchange on current status and emerging trends in innovative ceramic technologies and to identify strategic elements and new materials technology pathways for a sustainable future.

The session runs Monday afternoon and all day Tuesday (Jan. 23-24) in Coquina Salon F (Hilton). Two of the 25 presentations from this Summit are highlighted below.

“Innovations in bioactive ceramics and glasses for tissue engineering, drug delivery and regenerative medicine”
Speaker, Aldo Boccaccini, University of Erlangen-Nuremberg, Germany

Abstract: Beyond the well-established and expanding applications of bioceramics in medicine, e.g. as permanent implants and bioactive coatings, there is increasing interest in developing bioactive ceramics and glasses and their composites with biodegradable polymers, for applications in the fields of tissue engineering and drug delivery. Specific innovations involving the design and fabrication of multifunctional scaffolds that combine a variety of biodegradable polymers, signaling molecules, therapeutic drugs and bioactive ceramics will be presented. In this context, significant efforts are being devoted to investigating the effect of the dissolution products of bioactive glasses, both silicate and phosphate glasses, on cellular response, which includes understanding the effect of specific metallic ions (bioinorganics) on osteogenesis and angiogenesis during bone formation, both in vitro and in vivo. In addition, gaining further understanding of the antibacterial effect of specific ions released from bioactive glasses for combating infections more effectively is of particular interest. Specific research areas attracting large research efforts will be presented and promising avenues for future research activities will be discussed, highlighting the current needs and challenges for improving the overall performance of bioactive ceramics in tissue engineering and drug delivery.

“New ceramic membranes for energy- and environmental applications”
Speaker: Alexander Michaelis, Fraunhofer Institute for Ceramic Technologies and Systems IKTS, Germany

Abstract: Ceramic membranes are well established for micro-, ultra- or nano- filtration applications such as waste water purification. Further innovations require an improved control and reduction of pore size. This allows for new applications in gas separation and pervaporation systems. For this, pores sizes below 1 nm have to be generated using specific structural features of selected materials. Several new methods for preparation of such membranes are presented. In a first example we use the well know crystallographic cage structure of zeolites. Employing a new hydrothermal route allows for synthesis of dense zeolite films on porous substrates. It is shown that these membranes can be used for dewatering of bioethanol. In a further example we use carbon layers with well-defined lattice distances of 0.35 nm as a membrane for separation of hydrogen from gas mixtures. By further chemical modification of these carbon layers a well-designed adsorption selective behavior can be achieved as is demonstrated with membranes for purification of biogas. As a last example we present perovskite materials showing mixed conducting behavior. Due to an oxygen vacancy structure in the crystal lattice these materials can be used to generate oxygen which in turn can be used to improve the efficiency of combustion processes. Besides an improved energy balance in the combustion process this leads to reduction of CO2 emissions.

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Here’s what we are hearing (some information based on news releases):

Sandia National Labs presents H.C. Starck with supplier award

H.C. Starck was honored with the Oro “Gold” Award at the Annual Sandia National Laboratories Supplier Conference held Oct. 5, 2011 in Albuquerque, New Mexico. H.C. Starck was one of 15 manufacturing companies, out of 126 suppliers, selected as winners of the Oro Award. The company, which provides high quality materials in a timely manner that meet Sandia’s stringent quality requirements, received a commitment performance rating of better than 98% for on time delivery and quality. The Euclid, Ohio facility made significant improvements in customer satisfaction, product quality, and on-time delivery with its lean manufacturing initiatives and six sigma training.

Frac sand company Carbo Ceramics starts project in Wisconsin.

While the Wood County (Wisconsin) Board’s official stance on road usage agreements with frac sand haulers remains in limbo, one frac sand company is moving forward with plans to process sand in Marshfield. Carbo Ceramics Inc., which purchased about 40 acres on the former Wick properties at 2301 E. Fourth St. last year, held a groundbreaking ceremony Tuesday. The sand processing plant will start shipping product by mid-2012 and should be fully operational by the end of next year, said plant manager Steve Manier. Wood County officials have held talks with four frac sand companies opening operations here - Carbo Ceramics, Completion Industrial Minerals, Panther Creek Sand and Northern Frac Sand - about proposed road usage agreements requiring companies hauling the special type of sand to pay for any excessive damage caused by their trucks.

Comsol Version 4.2a unveiled at the COMSOL Conference in Boston

Comsol Inc. unveiled its Multiphysics version 4.2a, a major update of its market-leading multiphysics modeling and simulation environment. With the introduction of version 4.2a, which includes features that extend the reach of multiphysics analyses to new communities of engineers and scientists, Comsol has created a tightly-integrated analysis platform that offers a breadth and depth unmatched in the industry. Version 4.2a sees the debut of two new products, Particle Tracing Module and LiveLink for Creo Parametric, as well as many new features that bring greater modeling power to the users of COMSOL Multiphysics and its application specific add-on modules. Image-to-material conversion can shorten time to solution for image-based simulation dramatically. With this new capability engineers and scientists in industries such as life science and semiconductors can now bypass both geometry creation and computational-demanding meshing of microscopic details.

GreenCell Launches Its New Manufacturing Center

GreenCell, Inc. has launched a new manufacturing work center that can deposit conductive traces onto ceramic surfaces. Some composite ceramics are excellent conductors of electricity. Most of these conductors are advanced ceramics, modern materials whose properties are modified through precise control over their fabrication from powders into products. GreenCell’s innovative process allows them to deposit conductive inks onto their UltraTemp composite material. This process can be easily adapted the company’s line of igniters, sensors, fuel cells and heater panels.

Freeman Technology’s FT4 Powder Rheometer transforms powder testing capabilities

At AZO GmbH, a leading suppliers of automated raw material handling equipment, the introduction of the FT4 Powder Rheometer has revolutionised the company’s approach to powder characterisation. Replacing older shear cell equipment and a basic powder tester, use of the FT4 has dramatically reduced the time taken to reliably characterise a new powder and enhanced AZO’s ability to design and specify optimised solutions uniquely tailored to individual customer needs.

Malvern’s Materials Talks blog: One year old

David Higgs says, “I can scarcely believe that our blog is one year old today. It seems like a lifetime ago that our first post hit the internet and brought the world of Malvern materials characterization to a new audience. I must confess that there have been times when some of us have struggled to put “pen to paper” and produce relevant content about materials, industry and science. And I’ve had to charm and encourage the Malvern experts to provide interesting and useful articles. I hope you’ll agree when I say that I think they have excelled themselves and risen to the challenge more than once. I’m really grateful for their efforts and I hope they will continue to produce interesting articles about their work and play.

Cabot adds graphene technology to portfolio with IP agreement with XG Sciences

Under the agreement, Cabot Corp. will license intellectual property rights to XG’s graphene nanoplatelets technology, including detailed know-how regarding the manufacturing process. The move is consistent with Cabot’s commitment to provide customers with enabling materials solutions that deliver high performance, says Fred von Gottberg, Cabot vice president, New Business segment. Graphenes have the potential to be a dramatic step forward for our customers as they strive to find ways to make parts lighter, stronger or store energy more effectively. Our expertise in carbon black production, surface treatment and material science makes us a natural fit for delivering performance in automotive plastics, electronics packaging, advanced batteries and other applications with graphenes.

Zimmer introduces Invizia anterior cervical plate system

Zimmer Holdings Inc. introduced the inViZia Anterior Cervical Plate System at the 26th North American Spine Society annual meeting in Chicago, Ill. The system is intended for use in the temporary stabilization of the anterior spine during the development of cervical spinal fusions in patients with degenerative disc disease, trauma, tumors, deformity, pseudoarthrosis and failed previous fusions.

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3D visualization of the sintered 6P53B glass scaffolds using the Advanced Light Source’s synchrotron X-ray microcomputed tomography (left and top right) and a corresponding scanning electron microscopy image (bottom right). Credit: LBL.

Researchers in the glass and ceramics field seem to be stepping up the search for materials and fabrication techniques that can deliver strong, well-tolerated, customizable and, it’s hoped, inexpensive scaffolds for bone replacement and regeneration. The end product typically should be something that can serve as a temporary host for normal tissue to form matrices (that support and encourage cell growth, nutrient transport, vascularization, etc.) and also can be resorbed by the body in a planned and therapeutic way.

And, when looking at bones, one has to consider that not all of them function the same way. For example, the strength of tissue in long, load bearing bones (in the axis of the length of the bone) needs to be quite high.

The folks at the Lawrence Berkeley National Lab recently described some of the joint work its Advanced Light Source facility is doing with researchers at Imperial College London in using a special bioactive glass material—6P53B—and “robocasting” processing technique to produce samples that are both highly porous and strong (in the sense of compressive strength).

Those interested in this topic typically want to know how glass compositions compare to the well known 45S5 (”Bioglass”) glass material developed by Larry Hench. The main difference is that the 6P53B has K₂O and MgO that is absent in Bioglass, and contains more SiO_2; on the other hand, Bioglass has more Na₂O and CaO.

LBL has been working on using robocasting of 6P53B scaffolds and doing in vitro testing since at least 2006. Robocasting is a method of computer-controlled 3D deposition or “printing” of a slurry “ink” that has glass powder suspended in it. The computer builds a 3D structure layer-by-layer. Several other groups are using similar ink jet printing-like techniques for bioimplantable materials. Of robocasting, LBL researchers say on the ALS website, “This technique allows patterning and controlled fabrication, creating the scaffold following a computer model, and sintering the glass into the desired composition and shape. Therefore, it is possible to design glass scaffolds with variable degradation rates to match that of bone growth and remodeling.”

The LBL and Imperial College groups claims to be finding success in building scaffolds with compressive strengths in the range of what’s required for long, dense bones (~136 MPa), while retaining enough porosity to encourage cell growth and ion exchange. They report on their website, “The strength of this porous glass scaffold is ~100 times that of polymer scaffolds and 4–5 times that of ceramic and glass scaffolds with comparable porosities previously reported in the literature. The glass scaffold’s biological performance in both small animals (mice) and big (miniature pigs) is currently under systematic evaluation at the University of California, San Francisco.”

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Credit: F. Jacquot; Wikipedia.

Although they are somewhat light on the details, researchers at the Changzhou Institute of Light Industry Technology (CIT) say they may have found a way to address fatigue problems associated with two materials of interest for use as cartilage-like coating material for joint prostheses.

Led by Maoquan Xue, the CIT group wanted to see if they could improve the performance of UHMWPE (ultra-high-molecular-weight polyethylene) and PEEK (polyether ether ketone) that had an unfortunate knack of developing fatigue cracks. Presumably, that occurs because the long polymer chains carry the force from one point to the next.

They began by modifying UHMWPE and PEEK “cartilage” by adding unspecified ceramic particles and fibers, which alone, they say, improved the spatial structure of the material—but not enough to eliminate all fatigue wear. They hit on well-performing cartilage when they doused the mix with a gamma radiation burst. They says this irradiated combination breaks the main polymer chains without disrupting the overall structure of the artificial cartilage. The free radicals are recrosslinked, improving the mechanical properties and tribological properties of the materials.

According to a news release, the group believes the irradiated cartilage composite “could toughen up plastic joints in joint replacement surgeries and make them strong enough to last for years.”

The release continues, “As a result of the gamma burst, there is no way for microscopic fractures to be propagated throughout the material because there are no long stretches of polymer.”

Xue and others in the group say the composite has a leg up on alternative artificial joint coatings, such as nylon and nonstick polymers, because the latter produce debris that ultimately causes inflammation and pain. They also believe the composite is more “biocompatible” and may be a good host for the of addition of bone-generating cells.

The work was published in a paper in the International Journal of Biomedical Engineering and Technology (doi:0.1504/IJBET.2011.042495).

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