DC impedance of human blood using EIS: An appraoch to non-invasive blood glucose measurement

Abstract

This paper presents DC impedance characterization of glucose concentrations in human blood using Electrical Impedance Spectroscopy (EIS). Results are investigated also through two solutions other than human blood: 1) 0.9% NaCl, 2) Saline (NaCl 1.3gm, KCl 0.75gm, Na3C6H5O7 1.45gm, D-glucose 6.75gm in 500mL) for every 25mg/dl change of glucose in total 150ml solution. A rectangular current pulse of 1.5s duration with 1mA peak is applied to the sample and corresponding voltage is acquired with Agilent InfiniiVision 7000B Series oscilloscope and Matlab R2011a Instrument Control Toolbox. The circuit proposed for current injection and voltage acquisition requires only two electrodes would reduce electrode polarization and skin irritation greatly which is a major concern in many previous works use generally four electrodes. From voltage and current pulse, electrical impedance spectroscopy is formed using DFT in Matlab R2011a and then DC impedance are found getting the limiting value of EIS when ω = 0. Experimental results show linear variation in DC impedance with blood glucose concentration proves the feasibility of non-invasive blood glucose measurement using EIS.