MD+DI Online is part of the Informa Markets Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Using Laser Sintering to Improve Microimplant Integration

Diagram of a one-step laser sintering process conducted on the surface of a stent.

The Laser Zentrum Hannover e.V. (LZH; Hannover, Germany) plans on using laser sintering to improve the surface of microimplants. Its goal is to produce a porous structure on the surfaces of various types of implants, including stents used in the circulatory system and devices used in in the eyes, throat, nose, or ears. A surface containing porous structures can improve the implant's attachment to the surrounding tissue and enable it to dispense medication.

Because of their small surface area, it is difficult to integrate tiny implants into the surrounding tissue. The new method is geared toward promoting this integration. In addition, such implant surfaces offer little room for dispensing medications, which can promote acceptance of the implant in the body or prevent infections.

"Laser sintering can be used to modify the implant surface in a very specific manner," explains Matthias Gieseke, an engineer at LZH. "We hope to make the optimal structure for a number of applications."

Laser Splicing System Eliminates the Need for Rethreading

Exhibiting the ability to splice materials down to 0.002 in. thick, a laser cutting and welding machine is suitable for fabricating disposable devices.

Productivity gains are essential to manufacturers of medical devices. To optimize tool uptime in stamping operations used to fabricate medical device parts, Joining Technologies has introduced a new splicing system that it says will reduce downtime and eliminate the need for time-consuming rethreading procedures.

"[Users] can benefit from our Infinite Web 355 system for at least two reasons," remarks Dave Hudson, president of Joining Technologies. "Component manufacturers can enjoy longer oscillate-wound spools offered by coil suppliers that use our system. This means longer machine uptime between coil changes and less rethreading. In addition, by eliminating rethreading, the machine, when it is used on a stamping line, can reduce downtime and the risk of damaging tooling that can result from rethreading."

To run the machine, an operator places the trailing edge of a threaded coil and the leading edge of a virgin coil into the system. The system then automatically laser-cuts each coil end for proper alignment, brings them together, and welds them. It enables users to avoid rethreading by splicing a new coil to an existing, already-threaded coil. Once joined, the coils move as one web through the machine, eliminating the need for additional threading. "Our system essentially creates an infinitely long web," Hudson says. "Hence the name."

The Infinite Web 355 system represents a quantum leap in splicing equipment technology, according to Hudson. "While our system is able to splice materials as thin as 0.002 in., other portable systems can splice materials only 0.005 in. and larger." Another advantage of the system is its single-head configuration. "Conventional splicing equipment incorporates separate heads to perform cutting and welding operations," Hudson says. "But the Infinite Web 355 is designed with a single head for cutting and welding metal components."

With the ability to service multiple converting lines, the mobile, stand-alone machine requires only one electrical input and minimal operator involvement, Hudson notes. Its industrial PC-based control system features a touch screen interface, canned programs for selected alloys, and proprietary self-diagnostics to ensure optimal uptime. "The unit can handle most iron- and nickel-based alloys--steels and stainless steels--with thicknesses up to 0.040 in. and widths ranging from 0.125 to 14.0 in.," Hudson comments. "It also achieves weld penetration of 100% and tensile strengths of 60 to 95% of the base material."

"The system can process components for any kind of medical device that is made from coil stock," Hudson says. "Typically, it is used to process parts for disposable devices."
Joining Technologies Inc.
East Granby, CT

Wasted Energy May Someday Power Pacemakers and Other Implants

An energy cell can harvest its own operational energy to power microsensors.

Research and development of an innovative technology by scientists at Louisiana Tech (Ruston) doesn't appear to have been a waste of energy. The research team has designed and fabricated an energy cell that enables microscale electronic devices to harvest their own wasted energy for efficient powering of such medical products as electronic implants.

Power generation by way of harvesting  natural physical vibrations and thermal energy are areas that have already experienced breakthroughs this year. The Louisiana Tech team's technology represents yet another advancement in this promising area. Its technology, however, employs a piezoelectric, lead-zirconate-titanate cantilever coated on one side with a carbon nanotube film. Absorption of light or thermal energy by the film induces the cantilever to repeatedly bend while exposed to the stimulus. This cyclical bending motion, in turn, generates power.

"The greatest significance of this work is that it offers us a new option to continuously harvest both solar and thermal energy on a single chip, given the self-reciprocating characteristics of the device upon exposure to light and/or thermal radiation," says Long Que, assistant professor of electrical engineering. "This characteristic might enable us to make perpetual micro/nanodevices and micro/nanosystems, and could significantly impact the wireless sensory network."

In early experiments, the researchers demonstrated the nanotube-coated cantilever's ability to adequately power several low-power microsensors and integrated circuits; the device generated an electric potential of 10 V. The self-reciprocating energy cell also boasts the benefit of being able to harvest various energy sources, according to the researchers.

Details of the research were published recently in the journal, Applied Physics Letters.

South Dakota Beckons

These locales have more in common than it may seem at first. For example, all four would love to have more medical device manufacturers in their midst. There are often small contingents of economic development teams at trade shows, and they are typically from foreign countries that can offer favorable tax breaks or inexpensive labor. But has your company ever thought about relocating (or establishing a facility) in South Dakota? If so, a team from the state will be glad to answer your questions at MD&M Minneapolis. For the third year in a row, the Governor’s Office of Economic Development will attend the show to gauge and generate interest from medical device and bioscience companies.

“Medical device manufacturers and bioscience companies are targeted industries for South Dakota,” said Richard Benda, Secretary of the Department of Tourism and State Development. “These types of companies tend to appreciate South Dakota’s well-educated workforce, and they generally provide well-paying, quality job opportunities.”

Lead-Free Piezoelectric Material Could Serve as Replacement for PZT

Since the EU enacted the Restriction of Hazardous Substances directive (RoHS) several years ago, which bans several substances in electronics that are deemed hazardous, lead has become a material non grata. And though lead-based piezoelectric materials are currently exempt from the ban, some experts speculate that the materials may soon suffer a similar fate. To address this issue, materials engineers at the University of Leeds (UK) have developed a lead-free ceramic that could replace lead zirconium titanate (PZT) in many applications.

Piezoelectric materials such as PZT have lent their favorable attributes to a variety of medical applications, especially ultrasound transducers. In this capacity, PZT generates sound waves, transmits the echoes to a computer, and converts the information into a picture. The lightweight, lead-free ceramic developed by the Leeds researchers could offer a lead-free alternative without compromising performance, according to the researchers.

The researchers employed high-intensity synchroton radiation to demonstrate an electric-field-induced phase transformation in their ceramic. "We were able to probe the interior of the lead-free ceramic potassium sodium bismuth titanate (KNBT) to learn more about its piezoelectric properties," says Tim Comyn, lead investigator on the project. "We could see the changes in crystal structure actually happening while we applied the electric field."

An abstract of the research can be found in a recent issue of the journal Applied Physics Letters.


Carbon: The Building Block of Success

Carbon isn't just the building block of life; it's also apparently the foundation for success. This year's Nobel Prize recipients for both physics and chemistry were honored for their respective work with carbon in some form. And it's about time.

News of note this week, of course, is the bestowal of the Nobel Peace Prize in Physics for 2010 to Andre Gein and Konstantin Novoselov of the University of Manchester (UK) for their "groundbreaking experiments regarding the two-dimensional material graphene."  According to the Nobel Foundation, "Geim and Novoselov extracted the graphene from a piece of graphite such as is found in ordinary pencils. Using regular adhesive tape they managed to obtain a flake of carbon with a thickness of just one atom. This at a time when many believed it was impossible for such thin crystalline materials to be stable."

Since its discovery several years ago, graphene has demonstrated great potential for electronics applications owing to its strength, thin structure, and conductivity, even earning the nickname, 'the new silicon.' But while the novel carbon-based material is often championed for its potential in revolutionizing computers and other such applications, it does, in fact, also promise to improve medical device design and development.

Graphene could possibly be used for in vivo imaging. It may also enable the development of unique biomedical sensing applications, such as the graphene-based DNA sensor being investigated by Vikas Berry, an assistant professor of chemical engineering at Kansas State University. "Graphene's microscale surface area can be used for biointerfacing with cellular components, while its nanoscale quantum-confinement imparts it a high electronic sensitivity. With the electrons restricted to move in a single-atom-thick sheet, any small interference from the outside world brings a sensitive change in graphene's electrical properties," Berry told me last year for an editorial I wrote about graphene.

Along with earning accolades in the form of graphene, carbon also was at the root of work accomplished by researchers Richard Heck, Ei-Ichi Negishi, and Akira Suzuki. The scientists were awarded the Nobel Prize for Chemistry for "palladium-catalyzed cross couplings in organic synthesis." Their achievements in carbon-based chemistry help to overcome longstanding challenges associated with precisely linking carbon atoms together; because they are stable, the atoms do not react with each other easily.

"Palladium-catalyzed cross coupling solved that problem and provided chemists with a more-precise and efficient tool to work with. In the Heck reaction, Negishi reaction, and Suzuki reaction, carbon atoms meet on a palladium atom, whereupon their proximity to one another kick-starts the chemical reaction," according to the Nobel Foundation.

These groundbreaking advances in carbon have paved the way for future breakthroughs in a multitude of areas, including medical device design and development. It's fantastic that these pioneering spirits are finally getting the recognition they deserve. And it's not a bad week for carbon, either.

To learn more about graphene, read my editorial from last year regarding its potential impact, a blog post from July on a graphene-based antibacterial paper, or an article about how encapsulating nanoparticles in graphene shells could optimize nanoparticles for innovative medical breakthroughs. Also, Wired has a great overview of graphene and why it deserved the win on its Web site.

Use of CT Scans Triples in Past Decade

About 6% of 5,237 ER visitors received computed tomography or magnetic resonance imaging scans in 1998. Fast forward to 2007 and about 15% of 6,567 patients received them.

“We need to be smarter about imaging and we need to really look at the clinical situation and ask the question, ‘Does this patient really need the study?’” said David Waldman, chairman of the Department of Imaging Sciences at the University of Rochester Medical Center, in Rochester, New York, who wasn’t involved in the study. “Just because it’s easy now to get a CT scan doesn’t mean it’s the right thing to do.”

This Week In Brief: October 5, 2010

Engineered polymers provider TSE Industries Inc. (Clearwater, FL) has announced that it has received ISO 13485 certification for nonimplantable surgical devices. With the certification, the custom machine shop will be better equipped to serve the medical device industry in the processing of plastic and rubber parts.

Contract sterilization and ionization services provider Sterigenics International (Oak Brook, IL) has announced plans to begin construction of an EtO sterilization facility near San Jose, Costa Rica. The company anticipates that the facility will be operational by January 2012.

MedPlast, a manufacturer of molded components, has announced the completion of a Class 100,000 cleanroom at its West Berlin, New Jersey, manufacturing plant. The new facility was added to meet both the needs of existing customers that require a high level of compliance and cleanliness in the development, manufacturing, and assembly of medical products, as well as to accommodate several new customers that also require cleanroom manufacturing capabilities. The company has also added molding machines to increase capacity.

Denso Robotics (Long Beach, CA) has unveiled 14 robot application videos available for free viewing on the company's Web site and on YouTube. The videos feature the company's four-axis SCARA and six-axis articulated robots performing such diverse tasks as high-speed material handling, vision-guided packaging, applying adhesive film, bottle capping, machine tending, nut driving, product testing, and soldering.

Polyzen (Apex, NC) has redesigned its Web site with the intention of providing improved navigation and easier access to company and capability information. The company develops and manufactures critical medical components and devices, with expertise in materials and polymer science.

What Guidance Documents Do You Want FDA to Publish?

Through feedback from stakeholders, including draft language for guidance documents, CDRH expects to be able to better prioritize and more efficiently draft guidances that will be useful to industry and other stakeholders. This will be the fourth annual list CDRH has posted. FDA intends to update the list each year.

FDA invites interested persons to submit comments on any or all of the guidance documents on the list. FDA has established a docket where comments about the FY 2011 list, draft language for guidance documents on those topics, and suggestions for new or different guidances may be submitted (see ADDRESSES). FDA believes this docket is an important tool for receiving information from interested parties and for sharing this information with the public. Similar information about planned guidance development is included in the annual agency-wide notice issued by FDA under its good guidance practices (21 CFR 10.115(f)(5)). This CDRH list, however, will be focused exclusively on device-related guidances and will be made available on FDA's Web site prior to the beginning of each FY from 2008 to 2012.

To access the list of the guidance documents CDRH is considering for development in FY 2011, visit the FDA Web site

Medical electronics designers: Get your abstracts ready

  • Imaging
  • Diagnostics and Monitoring
  • Implantable Devices
  • Personal and Home Healthcare
  • Wireless/Networking
  • HCI (Human-Computer Interfaces)
  • Device Safety and Security

As a presenter in a class, you have the opportunity to teach to an audience of medical electronics OEMs. But be sure not to pitch your product or your company. That’s the best way to get your abstract rejected. I’ll be reading and evaluating many of the abstracts myself, so feel free to drop me a line ahead of time.

You only have until October 29 to submit your abstract, so now’s the time to get started.

Richard Nass