Non-invasive glucose monitoring

Introduction of a wearable non-invasive glucose monitor Cygness Inc. 

Sieg, A., R.H. Guy, and M.B. Delgado-Charro. 2004. Non-invasive glucose monitoring by reverse iontophoresis in vivo Application of the internal standard concept. Clin Chem 50 (8) 1383. 

Tierney MJ, Tamada Ja Potts RO, Jovanovic L, Garg S. Clinical evaluation of the GlucoWatch biographer a continual, non-invasive glucose monitor for patients with diabetes. Biosensors Bioelectronics 2001, 16, 621-629. 

H. H. Heise et al., Clinical Chemistry and Near-Infrared Spectroscopy Technology for Non-Invasive Glucose Monitoring, J. Near Infrared Spectrosc., 6, 349 (1998). 

Caduff A, Dewarrat F, Talary M, Stalder G, Heinemann L, Yu F (2006) Non-invasive glucose monitoring in patients with diabetes a novel system based on impedance spectroscopy. Biosens Bioelectron 22(5) 598-604... 

Tura AA, Maran Pacini G (2007) Non-invasive glucose monitoring, assessment of technologies and devices according to quantitative criteria. Diabetes Res Clin Pract 77(l) 16-40... 

Ultrasound and X-ray equipment are examples of diagnostic medical devices. In-vitro medical devices are distinguished from other diagnostic medical devices, in that a specimen must first of all be removed from the donor. A device worn by a diabetic that continually monitors their glucose via a non-invasive method (near-infra-red energy emissions) would be just regulated as a medical device, whereas a glucosemonitoring device that used a lancet to obtain a blood sample would be an IVD. 

Fischbacher C, Jagemann K-U, Danzer K, MUller UA, Mertes B (1995) Non-invasive blood glucose monitoring by chemometrical evaluation ofNIR-spectra. 24th EAS (Eastern Analytical Symposium), Somerset, NJ, November 12-16... 

Danzer K, Fischbacher C, Jagemann K-U, Reichelt KJ (1998) Near-infrared diffuse reflection spectroscopy for non-invasive blood-glucose monitoring. LEOS Newslett 12(2) 9... 

The ideal glucose monitoring system should be non invasive, should allow continuous or frequent monitoring over long periods without the need to replace the changeable parts (strip, transdermal patch, etc.), should interfere minimally with daily life, and, last but not least, should be low in cost. 

Alexeev V, Das S, Finegold DN, Grabowski J, Somayajula K, Asher SA. Photonic crystal glucose sensing material for non-invasive monitoring of glucose in tear fluid. Clinical Chemistry 2004, 50, 2352-2366. 

The isotope fluorine-18 has a half-hfe of 109 minutes and decays by positron emission therefore molecules containing this isotope can be monitored by positron emission tomography (PET), which is a technique that is especially useful for non-invasive in vivo study of metabohc processes [41]. For example, 2-fluorodeoxyglucose is transported into cells in the same manner as glucose but, after rapid phosphorylation, further metabolism is inhibited because of the fluorine, thus effectively trapping the radiolabelled... 

Because of the objective difficulties of the non-invasive approaches, another way to perform in vivo continuous monitoring has been to adopt the so-called minimally invasive methods, which measure the glucose concentration in the interstitial fluid of the skin. One of these is the insertion of a needle-shaped glucose biosensor directly into the subcutaneous tissue another is to insert just the microdialysis probe under the skin, while the determination of the metabolite occurs just outside the body. 

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