- About Us
- Career Center
- Nano-Social Network
- Nano Consulting
- My Account
|Fibroblasts growing on titanium alloy coated with nanotubes|
Titanium and its alloys have a leg up on all other materials used to make the orthopedic implants used by surgeons to repair damaged bones and joints. They are light, super-strong, and virtually inert inside the body. But whether the implants are destined for your knee, your hip, your spine or your jaw, the silvery metal has one big drawback.
By Marcia Goodrich
"Titanium has a mirror surface," says Tolou Shokufar, a PhD candidate in mechanical engineering-engineering mechanics. Cells don't adhere to it very well, so implants are often roughened up before they are placed in the body.
A good way to roughen titanium is to etch nanotubes into it, since they provide a superb surface for bone cells to grasp onto as part of the healing process. But etching nanotubes in the titanium alloy preferred by surgeons is not cheap. Conventional techniques require platinum, which costs over $1,700 an ounce.
Through her PhD work with Professor Craig Friedrich, director of the Multi-scale Technologies Institute, Shokufar has developed a less expensive way to etch nanotubes into the titanium alloy. In a weak solution of ammonium fluoride, she immerses two rods, one of the alloy, another of copper, and hooks them up to a power source. An electrical current flows into the copper, through the solution and out the titanium.
"It corrodes the titanium dioxide layer on the titanium in the form of a tube," Shokufar says, making nanotubes about seven microns long and a hundred nanometers in diameter. Growing the ideal tube takes about two hours.
Then she applies heat and pressure to the titanium alloy, annealing the nanotubes to give them a hydrophilic, crystalline structure. The surface not only attracts water, tests show it provides a friendly place for cells to grow. Shokufar has conducted experiments with fibroblasts—cells that make scar tissue—showing they grow faster on a layer of her titanium dioxide nanotubes than on the unaltered surface of the titanium alloy. Next, she aims to do a similar experiment with bone-growing osteoblasts.
Because the nanotubes are chemically identical to the titanium alloy, Shokufar expects that her innovation could be approved for medical use with relative ease. It may also have a wide variety of other applications, ranging from drug delivery to solar cells to hydrogen generation.
Her technique seems simple, but it didn't start out that way. "It took a lot of time to figure out," she says. "I'd spend days and days under the SEM, and when I went to sleep, I saw nanotubes inside my eyelids."
It's been worth it to see the perfect sheets of nanotubes grow under her care, however. "I really like them," she says. "They are like my babies."
About Michigan Technological University
Michigan Technological University (mtu.edu) is a leading public research university developing new technologies and preparing students to create the future for a prosperous and sustainable world. Michigan Tech offers more than 130 undergraduate and graduate degree programs in engineering; forest resources; computing; technology; business; economics; natural, physical and environmental sciences; arts; humanities; and social sciences.
For more information, please click here
Copyright © Michigan Technological UniversityIf you have a comment, please Contact us.
Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
|Related News Press|
News and information
Easier, faster, cheaper: A full-filling approach to making nanotubes of consistent quality: Approach opens a straightforward route for engineering the properties of single-wall carbon nanotubes July 19th, 2016
The NanoWizard® AFM from JPK is applied for interdisciplinary research at the University of South Australia for applications including smart wound healing and how plants can protect themselves from toxins July 26th, 2016
Accurate design of large icosahedral protein nanocages pushes bioengineering boundaries: Scientists used computational methods to build ten large, two-component, co-assembling icosahedral protein complexes the size of small virus coats July 25th, 2016