A new process of coating tiny particles called nanodiamonds allows direct delivery of chemotherapy drugs to keep cancers from growing back.

The nanodiamonds carrying the drugs eventually could be injected into a patient or implanted in the form of a patch to the location where a tumor was surgically removed to keep it at bay.

The technology is still several steps away from being used for patients. It’s currently in pre-clinical laboratory trials, then will advance to animals trials and is expected to be ready for human trials in five years, according to Dean Ho, a professor of biomedical and mechanical engineering at Northwestern University.

For patients with cancer, chemotherapy is often one of the most difficult aspects of treatment. The process being developed by Ho could make the process much easier with precise, localized delivery of medication. While nanodiamonds represent existing technology, the use of them for potential cancer treatment is new.  

The nanodiamonds are so small that hundreds of thousands of them could fit on the head of a pin, said Ho.

“When looking at the current needs of cancer treatment, the ability to have sustained and localized release is needed,” he said. “A lot of these nanocarbons [including nanodiamonds] are particularly relevant to cancer, so it seemed like a good fit.”

The nanodiamonds themselves don’t treat cancer, but are an efficient way of delivering the drugs that can. Treatment with chemotherapy as it stands now involves introducing the toxic agent to the patient’s entire body, which can produce unpleasant side effects.

Nanodiamonds can be used to deliver chemotherapy in two different ways. They can be injected or implanted with a small patch that looks like a piece of plastic wrap. Both methods would be less toxic than infusions used at present due to the slow release of the chemotherapy medications off the many surfaces of the nanodiamonds. The patch is expected to be particularly effective in the aftermath of surgery since it can be inplanted directly to the site where a tumor was removed.

Steven Rosen, the director of the Lurie Cancer Center at Northwestern, said he thinks that the nanodiamond technology has a future for the treatment of cancer.

“[Ho] is a very gifted young investigator with a lot of promise,” he said. "He’s a member of the cancer center," which endorsed his grant from the V Foundation. The foundation was founded by North Carolina State University basketball coach Jim Valvano, who died of cancer.

In addition to chemotherapy treatments, nanodiamonds can also hold other drugs. Ho said he sees the process as being useful for heart surgery, where a patch of nanodiamonds coated with an anti-inflammatory can be applied directly to the heart to prevent scarring or inflammation of the organ. Both conditions can slow the healing process for patients.

“You can link [nanodiamonds] to any type of drug,” Ho said. “They’re truly a platform.”

He sees nanodiamonds as providing a good delivery system not just because of the efficacy, but because they’re inexpensive, too.

“People might think diamonds are expensive to make—in fact they’re very economical,” Ho said. “They’re used for lubrication in the automotive industry. On a large enough scale, you can probably feasibly make them for several dollars per device.” The secret is that these are synthetic diamonds, he said.