A Colorado State University
mechanical engineering professor is in the first year of a new study to determine
whether nanotubes on titanium implants can deliver chemotherapy drugs and antibiotics
directly to skeletal implants, limiting the spread of drugs throughout the body
and reducing side effects on patients.
Cell growth on polymer wires made at CSU
Ketul Popat, who teaches in the university's School of Biomedical Engineering,
received a three-year $300,000 grant in 2008 from the National Science Foundation
to study nanomedicine - scaling down the size of drug delivery vehicles so that
the drugs can be delivered directly to the target organs with appropriate delivery
rates. One of the first papers on the study appeared in the January issue of
Colorado's Bioscience Discovery Evaluation Program, which aims to foster development
of the bioscience industry in the state, also recently approved a grant of $57,000
for the research.
Popat and his four students are investigating whether tiny tubes of titanium
adhered to the implant can be used to deliver drugs and increase bone growth
on the implant surface. Titanium, which is an exceptionally hard and scratch-resistant
material, has been used in prosthetic devices since the 1970s. Popat's team
is taking the research to the next level: Will increasing the surface area of
the titanium with a pattern of tiny tubes allow drugs to be delivered in a controlled
way that will help regenerate the bone and keep the tissue healthy?
"We hope these nanotube arrays will mimic the complex geometries of natural
tissue and will provide a porous mesh for the growth and maintenance of healthy
cells," Popat said.
Popat said his team has hypothesized that applying nanotubes to the implant
surface will result in increased cell growth. This cell growth on the implant
surface will enhance the bond between the titanium implant and the bone, helping
implants last longer. Typically implants must be replaced every eight to 10
years. However, by applying these nanotubes to the implant, they can be made
more permanent inside the body, thus preventing further complicated surgeries
"Ultimately, if this kind of drug delivery system is found to be successful,
it's going to improve the quality of life for people," Popat said. "Chemotherapy
delivers up to 60 times more drugs than what is needed. We could release the
drug for shorter or longer periods of time and keep the drug targeted to the
tissue where is it needed so you won't realize you're taking a drug and there
won't be any side effects."
Popat joined the Colorado State University College of Engineering in January
2008 as an assistant professor. He is working with Craig Grimes at Pennsylvania
State University on the research.