Abstract: A blood chemistry analyzer for determining the concentration of various chemical compounds or analytes in a patient's blood in a non-invasive manner employs a plurality of electrodes, an isotonic bath, a spectrophotometer, and a control unit. Adhesive electrodes are attached to the patient's skin such that the patient's entire peripheral blood supply system is analyzed. The controller provides a signal to the electrodes that causes the electrodes to develop an electrical charge, or potential, having a magnitude proportional to the detected charge for the analyte of interest. This potential is transmitted to an isotonic bath where it causes a portion of the dissolved salts to separate into anions and cations. The amount of separation is proportional to the magnitude of the electrical potential. Predetermined volumes of the anion/cation saturated isotonic solution are piped into reagent wells containing a reagent corresponding to the specific blood analyte of interest.