This invention places a drug delivery system inside a prosthetic implant to circumvent the physical issues encountered after fitting the implant. Implants being relatively large in size would be able to house the drug-carrying device inside them without compromising the structural integrity or the functionality of the prostheses. Capsules containing multiple reservoirs filled with different drugs could be released simultaneously. This application could further be extended to using such drug-carrying capsules in cardiovascular stents through which slow and sustained release of drugs could be achieved to prevent inflammation in the short term, and restenosis in the long term. Once the capsule has drained out, the drug inside will remain in the implant and can be considered a part of the implant for the future. The implant reservoir may also be refilled via minor surgery until needed.

A drug-carrying capsule was developed that can be implanted into the body for a sustained and controlled drug release. The capsule presents nanochannel silicon membranes for passive (driven by a gradient of concentration across the membrane) and active drug release (driven by electro-osmosis). A constant passive release of several molecules was achieved by judiciously tailoring the size of the nanochannels.

A drug eluting implant would lead to a quicker and more comfortable recovery. Compared to routine administration of drugs in plasma, less of the drug would be administered and a higher local concentration would be achieved. This would result in fewer side effects and a minimally invasive way of delivering drugs. Since both the implant and the drug-carrying capsule are biocompatible, they are completely safe to use and would not be a concern even after the drug has been delivered. A cyclic or non-constant drug release could be achieved by means of electro-osmosis.

This work was done by Alessandro Grattoni and Aman Mann of the University of Texas Health Science Center at Houston; and Randy Goodall, Lee Hudson, and Sharath Hosali of NanoMedical Systems, Inc. for Johnson Space Center. NASA is seeking partners to further develop this technology through joint cooperative research and development. For more information about this technology and to explore opportunities, please contact This email address is being protected from spambots. You need JavaScript enabled to view it.. MSC-24539-1

NASA Tech Briefs Magazine

This article first appeared in the May, 2016 issue of NASA Tech Briefs Magazine.

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