Carbon nanotubes encapsulated within a hydrogel, allowing them to be implanted under the skin.
Carbon nanotubes are nano-scale, cylindrical structures composed of carbon chains, with unique properties that make them particularly attractive for use in the construction of various nanotechnologies. Nanoscale sensors and devices have shown to be increasingly relevant in the medical world, as they seem to address many of the prominent issues that modern medicine is not yet able to confront, or address cost-effectively. Researchers at MIT are taking advantage of the unique properties of carbon nanotubes, namely natural fluorescence in a spectral region that has little interference from biological media, to construct biosensors that monitor the presence of nitric oxide, an important signaling molecule whose levels fluctuate in cancer cells. The sensor consists of a nanotube segment, wrapped in a particular DNA sequence, which binds to the target molecules, altering the fluorescent luminosity. The technology is currently being adapted for use in diabetic patients, by altering the sensor to bind to glucose. Theoretically, the technology could be adapted to any number of biomolecules by altering the DNA sequence used in the sensor.
What makes this technology more appealing, however, is the prospect of long term monitoring when localized subdermally. The nanosensor can be injected directly into the bloodstream for short-term use, or placed under the skin of a patient for uninterrupted monitoring for over a year, according to the research. This is accomplished by embedding the sensor in a biocompatible gel that can protect the technology for up to 400 days; the researchers believe it could potentially last longer. Furthermore, when injected into the bloodstream, the nanosensor was observed to pass through the heart and lungs without causing damage or clumping, an important factor for venous sensing technology.
Hopefully, the development of this technology will be successful, as it could be extremely helpful in monitoring the progression of diabetes, cancer, or virtually any other illness that can be gauged through the presence of biomarkers.
Nature nanotechnology: In vivo biosensing via tissue-localizable near-infrared-fluorescent single-walled carbon nanotubes…
MIT: New implantable sensor paves way to long-term monitoring…
