Abstract: A non-invasive method for measuring blood glucose concentration using glucose present at the mucosal surface of a living being is provided. The method includes the steps of positioning a glucose oxidase membrane on the mucosal surface, providing oxygen for peroxidative oxidation of the glucose present thereat, electrically measuring the amount of hydrogen peroxide product and calibrating that amount to determine blood glucose concentration. Also provided are electrode devices suitable for carrying out the method.

Abstract: There are disclosed a method and an apparatus for measuring moisture content of skin. The skin surface is illuminated with polarized light incident at the Brewster angle. The degree of polarization of the light refracted within the skin and reflected out is measured. The measurement is a function of the refractive index of the skin which, in turn, is a function of the moisture content. To avoid measurement variations due to such things as skin color, output readings are in the form of a ratio of the reflected polarized light intensity to the reflected total light intensity.

Abstract: There are disclosed apparatus and methods for performing in-vivo measurements of enzyme kinetics on the epidermis and mucous membranes of a subject. One or more reactants are placed on a predetermined area of the skin in order to react with the enzyme or other biological substance of interest. At least one physical characteristic of one or more of the reaction products formed is measured. Changes in enzymatic or related activity in response to various stimuli can be observed by continuously monitoring the physical characteristic of the reaction product while certain controls are varied, thereby providing dynamic information not previously obtainable.