Nanofountain Probe array formation. Credit: Ho and Espinosa

Nanofountain Probe array formation. Credit: Ho and Espinosa

Two Northwestern University researchers believe they have developed a new dual-use tool and methods for delivering drugs and other nanoscale therapeutic materials to cells using coated nanodiamonds. The researchers, Horacio Espinosa, professor of mechanical engineering, and Dean Ho, assistant professor of mechanical and biomedical engineering, at Northwestern’s McCormick School of Engineering and Applied Science, call their tool a Nanofountain Probe

To understand the probe’s abilities, Espinosa and Ho use two analogies. First, they say it’s like a fountain pen containing an “ink” of drug-coated nanodiamonds that can then be written with. The other analogy is to a syringe – albeit a very tiny one – so small that it can deliver materials to individual cells. This could aid in the precise delivery of toxic chemotherapy drugs in cancer patients.

The research group has already begun trials in which they inject doses of nanodiamonds into both healthy and cancerous cells.

In a story on the McCormick School’s website, Ho said, “This allows us to deliver a precise dose to one cell and observe its response relative to its neighbors. This will allow us to investigate the ultimate efficacy of novel treatment strategies via a spectrum of internalization mechanisms.”

In a different application, they are using the nanofountain probe to lay down arrays of drug-coated nanodiamonds on glass substrates. This array-production aspect of their work mainly serves to provide a  proof-of-concept for future manufacturing of  patch-like devices for the delivery of nanomaterials. The probe provides a method for controlling dosage and precisely distributing the materials upon the substrate. The patch approach, itself, is advantageous because it theoretically provides a way of delivering precise, low-level amounts a chemotherapy drugs for months at a time. Ho has already worked with a polymer patch covered with a layer of drug-coated nanodiamonds, which moderate the release of the drug.

The use of films containing drug-coated nanodiamonds isn’t particularly novel, but Espinosa and Ho are taking it farther by offering a method to have patterned arrays composed of multiple drugs. Ho says. “This allows high-fidelity spatial tuning of dosing in intelligent devices for comprehensive treatment.” They claim the patterning resolution represents an improvement of three orders of magnitude over previous schemes to deposit nanodiamonds.

“One of the most significant aspects of this work is the Nanofountain Probe’s ability to deliver nanomaterials coated with a broad range of drugs and other biological agents,” Espinosa says. “The injection technique is currently being explored for delivery of a wide variety of bio-agents, including DNA, viruses and other therapeutically relevant materials.”

Ho and Espinosa also think the high-resolution ability of their probe will also be a benefit to the development of nanoelectronics, providing a controlled way to “seed” the growth of diamond thin films. Nanodiamonds have also proven effective in seeding the growth of diamond thin films