Abstract:
Diabetes is widespread in Pakistan and the patients must go through the pain of
repeated pricking and thereby are prone to infection. The sensor developed in this
study can detect glucose from saliva and save people from the pain of pricking. This
non-enzymatic sensor has a longer shelf life and easy storage without being affected
by environmental factors like temperature and humidity. The sensor works on a 3-
electrode system: working electrode, counter electrode, and reference electrode. The
working electrode is of primary significance as it detects glucose by oxidizing it. We
devised two methods for making the working electrode: (1) Copper-oxide electrode
with CuO nanoparticles grown by the electrochemical method and (2) Copper-oxide
electrode with CuO nanoparticles grown by LASER ablation. The X-ray diffraction
(XRD) was used for phase analysis of the developed material to confirm the synthesis
of copper oxide. Scanning Electron Microscopy (SEM) was used to analyze the surface
morphology and particle size of the synthesized material to confirm the presence of
particles under the 100-nanometer range. Optical Profilometry was used to analyze
the topography and roughness of the synthesized copper oxide. Furthermore, cyclic
voltammetry (CV) was performed to analyze the electrochemical behavior of the
sensing material, and the redox reactions were studied for solution concentration and
corresponding peak current to determine the sensitivity and limit of detection of the
sensor. The Glucose sensing and electrochemical results of the working electrode
developed by LASER ablation are 5X better than the results of the working electrode
developed by the electrochemical method. The sensitivity achieved for LASER treated
electrode is 770 µA/mM of glucose with a limit of detection of 0.44 mM. A lower
sensitivity of 578 µA/mM of glucose with a limit of detection of 11.1 mM was achieved
for the electrochemically grown copper oxide electrode.
