Nanotube Tattoo for Blood glucose monitoring
Scientists The Massachusetts Institute of Technology, working under the leadership of Professor Michael Strano, have developed a new type of monitoring of glucose levels in human blood. Their proposed method, based on the introduction of glucose-sensitive carbon nanotubes under the skin, will relieve patients with diabetes mellitus from the need to regularly measure glucose levels using traditional glucose meters.
The study, the results of which were published in 2008 in the New England Journal of Medicine in the article "Continuous Glucose Monitoring and Intensive Treatment of Type 1 Diabetes", showed that constant monitoring of blood glucose levels helps adults with diabetes control their condition more effectively. The fact is that relatively short sharp rises in blood glucose levels, for example, after a meal, can have a detrimental effect on the body of a diabetic patient. Therefore, timely detection and prevention of these rises is extremely important for the preservation of the health of patients with this disease.
Unfortunately, the portable devices that exist today do not provide a sufficient degree of accuracy and need daily calibration. Therefore, diabetics who care about their health are still forced to prick their finger several times a day and squeeze out a drop of blood on the test strip of the glucose meter.
The principle of operation of most existing devices for continuous monitoring of blood glucose levels is the introduction of a glucose-splitting enzyme glucose oxidase to a person. The interaction of the electrode adjacent to the patient's skin with hydrogen peroxide – a by–product of this reaction - allows you to indirectly assess the level of glucose in the blood. However, none of these sensors are approved for use for more than seven consecutive days.
The sensor proposed by the authors is based on the technology described in the December 2009 issue of ACS Nano magazine in the article "Modulation of Single-Walled Carbon Nanotube Photoluminescence by Hydrogel Swelling". Such a sensor consists of glucose-sensitive carbon nanotubes enclosed in a polymer shell. When interacting with glucose, the nanotubes begin to emit a fluorescent glow in the near infrared part of the spectrum. The intensity of the fluorescence emitted in this case reflects the concentration of glucose.
Currently, researchers are developing "ink" from nanoparticles suspended in solution. Such ink will be used to inject under the skin of the patient's hand in the form of a kind of "tattoo", the service life of which will be several months.
To read the results over the "tattoo", the patient will need to wear a sensor similar to a wristwatch. This sensor will emit light of the desired part of the spectrum to the sensor and continuously register the intensity of the response glow of the nanotubes located under the skin. An important aspect is that, unlike most fluorescent molecules, nanotubes do not break down under the influence of light and the intensity of their fluorescence does not decrease even under constant illumination.
The developers note that clinical trials of the new sensor are still far away, but they plan to test its effectiveness on animals in the near future.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru according to the Massachusetts Institute of Technology: 'Tattoo' may help diabetics track their blood sugar.
31.05.2010