Noninvasive glucose monitoring

Patients with type 1 diabetes feel that blood glucose monitoring is a particularly burdensome factor of diabetes management. The self-injury necessary for blood sampling is much more painful than the injection of insulin. There is therefore a thoroughly understandable desire for a pain-free, i.e. noninvasive, glucose monitoring and efforts to develop such products have been made for decades. This article presents a summary of the various physical possibilities for an injury-free glucose monitoring and some examples of developments of noninvasive glucose measurement systems. A particular problem is the unfavorable signal-to-noise ratio, i.e. the filtering out of the actual glucose signal from the noise created by various other factors is extremely difficult. Nearly all systems for noninvasive glucose measurement presented so far represent only functional patterns with which optimistically sounding results can be achieved under defined laboratory conditions. Of the few instruments which have an approved CE label, i.e. already on the market or will soon come onto the market, none has achieved a proven suitability under routine daily life conditions of patients. In the past such approaches were euphorically presented to the public only to find that the end effect did not live up to expectations. However, it could be that the rapid progress in microtechnology and nanotechnology will promote the development of noninvasive measurement systems in such a way that the breakthrough will actually be achieved.