Noninvasive in vitro measurement of pig-blood D-glucose by using a microwave cavity sensor

Department of Physics and Basic Science, Sogang University, Seoul, Republic of Korea.
Diabetes research and clinical practice (Impact Factor: 2.54). 02/2012; 96(3):379-84. DOI: 10.1016/j.diabres.2012.01.018
Source: PubMed


We have developed an electromagnetic microwave cavity sensor based on the resonant frequency shift for real time measurement of the glycemia in pig blood. We could determine the concentration of d-glucose in pig blood in the range of 150-550mg/dl at the resonance frequency near 4.75GHz with a bandwidth of 300MHz. The change in the d-glucose concentration in blood brings microwave reflection coefficient S(11) changes of about 6.26dB and resonance frequency shifts of about 11.25MHz due to the electromagnetic interaction between the cavity resonator and the blood filled plastic tube inserted into the cavity. This proposed system provides a unique approach for real time noninvasive and contactless glucose monitoring.

Download full-text


Available from: Arsen Babajanyan, Feb 02, 2015
  • Source
    • "A similar structure has been later used by the same authors as a biosensor for monitoring the glucose concentration in water [14]. A microwave biosensor based on a waveguide cavity resonator has been developed in [15] for non-invasive in-vitro measuring of pig blood D-glucose. A device based on an open-ended coaxial resonator embedded in a microfluidic chip has been recently proposed in [16] for compositional analysis of solvents at microwave frequencies. "
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents 1 the design, fabrication, and characterization of a microwave resonator as a tool for concentration measurements of liquid compounds. The sensing device is a rectangular waveguide cavity tuned at 1.91 GHz, which exploits the fundamental TE101 mode in a transmission-type configuration. The coupling structure is optimized by means of a finite element code so as to achieve a high Q-factor. According to the type of substance inside the mixture, its concentration is conveniently related to changes of the S21 scattering parameter (transmission coefficient) in terms of: 1) resonance frequency; 2) 3-dB bandwidth; and 3) amplitude at the resonance frequency. Experimental tests on liquid solutions in controlled conditions are presented to evaluate the performance of the device.
    Full-text · Article · May 2013 · IEEE Sensors Journal
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The main objective of this contribution is to explore the absorption of electromagnetic microwaves in different human body regions for non-invasive glucose monitoring (NGM). Recently, the use of dielectric measurements for the purpose of NGM has been an area of much interest. However, currently no existing report can explore the power dissipation of electromagnetic waves for the NGM. This work is based on established empirical models of human tissue and standard human body models of the Electromagnetic (EM) simulation tools, such as CST Voxel Model. The Specific Absorption Rate (SAR) is investigated for various frequencies and different regions of the human body to estimate the optimum real-world scenarios for non-invasive glucose monitoring (NGM). Empirical models of dielectric properties for estimating the blood glucose concentrations are applied at frequency range from 1 GHz to 10 GHz and blood glucose concentration of hyperglycemia (300 mg/dl), hypoglycemia (40 mg/dl) and euglycemic (100 mg/dl). A comparative evaluation of SAR measurements for blood in free space and blood in body's vessels is presented in context of investigating the effect of power dissipation for dielectric NGM measurements.
    Full-text · Conference Paper · Aug 2013
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A continuous glucose sensor employing radio frequency (RF) signals has been developed using the biocompatible material Silicon Carbide (SiC). Unlike biosensors that require direct contact with interstitial fluids to trigger chemical reactions to operate, this biocompatible SiC sensor doesn't require a direct interface. The sensing mechanism is based upon a shift in resonant frequency as a function of change in glucose levels which electrically manifests itself as a change in blood permittivity and conductivity. For invivo applications the antenna sensor needs to operate inside the body environment, and it has been determined that the best operational location of this biocompatible SiC biosensor is within fatty tissue in close proximity to blood vessels. To test the sensor as a function of glucose level, measurements using synthetic body fluid (SBF), which is electrically equivalent to blood plasma, and pig blood were performed. Changes in sensor performance to varying glucose levels were measured and a shift in resonant frequency to lower values observed with increasing glucose level. In-vitro sensor performance demonstrated that the sensor showed a dose dependent response to glucose concentration from 120 mg/dl to 530 mg/dl. A shift of 40 MHz and 26 MHz for blood mimicking liquid and pig blood was observed corresponding to 97 KHz and 67 KHz shift per 1 mg/dl change in blood glucose.
    Full-text · Conference Paper · Nov 2013
Show more