A Driving Force in Biomedicine
The Houston Methodist Research Institute is gaining momentum on new ways to use carbon fiber materials in biomedicine. Earlier this year, the institute and Italian luxury sports car manufacturer Automobili Lamborghini announced a partnership to study innovative medical applications for new carbon fiber materials.
“We may be in different fields, but they are the best of the best of the best,” said Mauro Ferrari, Ph.D., president and CEO of Houston Methodist Research Institute. ”We always want to be working with people who are at the top of whatever it is they’re doing. We make it a point here to interpret the very best technologies that are out there in all fields of technologies worldwide, connect and bring them into clinical research and, ultimately, into clinical practice.”
Lamborghini first began exploring carbon fiber materials in 1982, when employees who previously worked for Boeing applied their aeronautic engineering skills to high-performance sports cars. Since then, the supercar manufacturer has made a name for itself in the research and development of carbon fiber technology for the automotive field. Now, Lamborghini has set its sights on medicine.
Alessandro Grattoni, Ph.D., chair of the department of nanomedicine at Houston Methodist Research Institute, will lead the three-year study to evaluate the biocompatibility of Lamborghini’s carbon fiber composite materials in humans. These materials could potentially be used to create stronger, lighter and safer medical tools—including implantable prostheses and nanotechnology-based devices.
“The most exciting aspect of the study is the investigation of new materials. Out of new materials you can generate new ideas, devices and technologies,” Grattoni said.
The conventional structure of carbon fiber consists of long, thin strands of material that range from .005 to .010 mm in diameter. These fibers, which are made of tightly interlocked carbon atoms, are woven together to create sheets of cloth-like material that are placed over large molds and embedded in epoxy resins to contain their shape.
In contrast, the new carbon fiber material uses short carbon fiber strands, which opens up a world of opportunity in 3-D printing. Lighter, more moldable materials of different sizes, shapes and complexity might be possible.
“With 3-D printable materials you can create structures and devices that are tailored specifically for each patient. This gives you an edge in the personalization of technologies and treatments,” Grattoni said.
Most prosthetic implants for reconstruction around the body—including the skull, mandible or femur—are built out of titanium, with an expensive and cumbersome manufacturing process. External fixators, used in orthopedic surgery to support and stabilize fractured bone, are often made of stainless steel or titanium, as well. These materials are visible on X-rays and can obstruct the view of the bone and surrounding anatomy.
Carbon fiber, on the other hand, is radiolucent to X-rays, making it a particularly useful composite material for medical applications where imaging is key.
“Carbon fiber materials are not radio-opaque. In orthopedic applications, carbon fiber composites may offer high mechanical properties without obstructing radiographic assessments of bone, fractures or defects being treated,” Grattoni said. “These same properties make these materials useful tools for neurosurgery, where imaging is critical to guide you to the right place.”
In the field of nanotechnology, Grattoni has already developed an implantable drug delivery system that contains dry reservoirs of drugs that are released through a silicon nanofluidic membrane. As the drug is released from the reservoir, it diffuses through the membrane to the body at a constant and controlled rate.
“This has allowed us make implants that deliver drugs always at the same rate, always the same dose for many, many months, potentially years,” Grattoni said.
But patients may require different doses. The nanochannels need to be tailored to treat each individual. Accordingly, patients may need different implant sizes and shapes. The implant drug reservoirs are currently made of implantable titanium or a medical-grade plastic called polyether ether ketone. Since the new carbon fiber material is moldable, 3-D printable and highly customizable, it could allow for more robust and thinner structures that can be tailored in size and shape to fit each individual patient.
“Additionally, the shape of some carbon fiber materials can be modified via an applied electrical potential,” Grattoni said. “It’s a very cool feature that has been used in the automotive industry with Lamborghini cars.”
Carbon fiber that can alter its shape could be used to develop nanogates that can be opened and closed remotely to control drug release, Grattoni explained.
“A system such as that would allow you to modulate drug release via Bluetooth,” he said. “Doctors could interview patients via phone or internet and adjust the dose remotely.”
With the diversity of expertise in engineering and medicine, this unlikely pairing of a hospital research institution and a luxury sports car manufacturer will likely produce cutting-edge solutions.
“It is perhaps unusual, but that is by design how we think of things in a different way,” Ferrari said. “We are not incremental. We are divergent.”