Study of Noninvasive Sampling of Subcutaneous Glucose by Reverse Iontophoresis

As the symmetry of the iontophoresis technique, the reverse iontophoresis technique of extracting and analyzing glucose from the subcutaneous space to the skin surface was described in this paper, as a preliminary step towards the development of noninvasive extracting and analyzing glucose concentrations of human body. Reverse iontophoretic experiments on glucose in sodium chloride solution were performed. The extracted current density was constant 0.5 mA/cm² and glucose concentration under naked mouse skin was changed in a range of 0 ~ 18 mM. A sensitive amperometric biosensor was designed and prepared for the measurement of the glucose extracted from the subcutaneous space. Our results indicate that reverse iontophoretic extraction has a good correlation with the subcutaneous glucose concentration (r=0.98, n=7). Further research also demonstrates that by addition of EDTA into the cathodal electrolyte could augment the glucose transportation across the naked mouse skin by reverse iontophoresis.