Diabetes is a metabolic disorder, which results from insulin deficiency and hyperglycemia and is reflected by blood glucose concentrations being outside the normal range of 80-120 mg/dL (4.4-6.6 mM). The novel system is presented that utilises change in the value of impedance as an instant indicator of the glucose level of the solution, brought in contact with a sensor. The glucose sensor was developed using the enzyme glucose oxidase (GOx) immobilized within the poly(o-Phenylenediamine) (PPD). O-Phenylenediamine (o-PD) was prepared in an acetate buffer solution with pH5 and then mixed with GOx. The resultant GOx/o-PD mixture was deposited onto Au thick film interdigitated electrodes and electrochemical immobilization of the enzyme was performed using the bulk electrolysis with coulmetry technique at 3 V for 900 s.

Through a catalytic enzymatic reaction between glucose and glucose oxidase the biosensor generates hydrogen peroxide and its response therefore is based on the electrochemical oxidation of H₂O₂ [1]. The electrochemical formation of polymer films enables to make a glucose sensor with a controlled thickness, which is reproducible and could be miniaturized.

The sensor was connected to the Analog devices AD5933 impedance converter system, which measured a change in impedance when different glucose concentrations were deposited onto the sensor within 1-7 mM glucose range.

The well-manifested change in the value of capacitances is directly related to the concentration of the glucose in the solution being tested. Moreover, the response of the sensors to the glucose change was in the order of 10 s, similarly to [2].

[1] S. Cosnier et al, J. Electroanalytical Chemistry 469(2), pp. 176-181, 1999.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/19073 must be provided.

1. Development of handheld DNA Sensor for foodborne pathogen detection: Fundamental factors & Challenges
2. SnO₂, TiO₂, and TiO₂/ZnO thick film pressure sensor with interdigitated electrodes
3. Novel Higher Sensitivity Silicone Based Capacitive Pressure Sensors For Biomedical Applications