Noninvasive blood glucose monitoring.

The concentration of glucose in the blood may soon be measured noninvasively, without puncturing the finger to obtain a drop of blood. Current prototype devices for this purpose require greater accuracy and miniaturization to be commercially viable. No such device has been approved for marketing by the U.S. Food and Drug Administration. The technology used for noninvasive blood glucose monitoring involves either radiation or fluid extraction. With radiation technology, an energy beam is 1) applied to the body, 2) modified proportionate to the concentration of glucose in the blood, and 3) measured. The blood glucose concentration is then calculated. With fluid extraction technology, a body fluid containing glucose in a concentration proportionate to the blood glucose concentration is extracted and measured. The blood glucose concentration is then calculated. The most promising technologies are 1) near-infrared light spectroscopy, 2) far-infrared radiation spectroscopy, 3) radio wave impedance, 4) optical rotation of polarized light, 5) fluid extraction from skin, and 6) interstitial fluid harvesting. Each method has features predictive of commercial viability, as well as technical problems to overcome.