THE ELECTROCHEMICAL EVALUATION OF GLUCOSE BIOSENSOR BASED ON INCORPORATING PLATINUM NANOSTRUCTURES, GLUCOSE OXIDASE, AND POLYMERIZED 1,10-PHENANTHROLINE-5,6-DIONE

Gustė Jakučiūnaitė1, Natalija German2, 3

1 Department of Analytical and Environmental Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Vilnius, Lithuania

2 Department of Immunology and Bioelectrochemistry, State Research Institute Centre for Innovative Medicine, Vilnius, Lithuania

3 Department of Chemistry and Bioengineering, Faculty of Fundamental Sciences, Vilnius Gediminas Technical University Vilnius Tech, Vilnius, Lithuania

[email protected]

Electrochemical biosensors are widely recognized today as highly sensitive and efficient tools for detecting various substances. They play a significant role in disease diagnosis and enable identifying a wide range of targets, spanning pharmaceutical and clinical fields to industrial, food, and environmental sectors [1]. Electrochemical biosensors incorporating glucose oxidase (GOx) are among the most effective tools for glucose measurement, offering high selectivity, sensitivity, and low detection limits. Developing a second-generation glucose sensor requires a mediator to facilitate electron transfer between the enzyme and the electrode through oxidation-reduction reactions. Polymerized mediator, 1,10-phenanthroline-5,6-dione (pPD), plays a crucial role in improving overall sensor performance, ensuring higher sensitivity, stability, and reliability in glucose detection. Due to their unique structural, optical, and catalytic properties, platinum nanostructures (PtNS) exhibit remarkable catalytic activity and are widely used in electrochemical analysis. They are universally recognized for their outstanding ability to catalyze the oxidation and reduction of hydrogen peroxide, attributed to their high active surface area and favourable latent planes compared to bulk metals. Additionally, their biological compatibility makes them highly attractive for the development of oxidase-based sensors [2]. In this study, the main aim to highlight the importance of all chemical compounds in developing an optimal system for creating a biosensor that can be widely used in today’s industry. The modification’s process of electrode’s surface is shown in Figure 1. Analysing the cyclic voltammograms provides information about the increased current when pPD is added, proving that pPD enhances the system’s conductivity. GOx likely facilitates electron transfer, as it is an enzyme capable of catalyzing redox reactions. When these components work together, a synergetic effect is observed, ensuring excellent reversibility of oxidation and reduction processes. The presented calibration curves correspond to hyperbolic functions and follow Michaelis-Menten kinetics. The depicted dependencies illustrate the CE/PtNS/GOx/pPD system (\(\Delta \mathit{I_{max}}\) = 42.2 \(\pm\) 2.8 \(\mu\)A; 6.64%; K\(_{M}\) = 230 mmol/L). This study demonstrates that the incorporation of pPD, GOx, and PtNS significantly improves the performance of glucose biosensors. The findings suggest that further optimization is needed to enhance long-term stability for practical applications in glucose monitoring.

Figure 1
Fig. 1. A schematic visualization of an electrode modification process, featuring cyclic voltammograms.


[1] P. K. Kalambate et al., “Electrochemical (bio) sensors go green,” Biosensors and Bioelectronics, vol. 163, p. 112270, May 2020, doi: 10.1016/j.bios.2020.112270.

[2] H. Teymourian, A. Barfidokht, and J. Wang, “Electrochemical glucose sensors in diabetes management: an updated review (2010–2020),” Chemical Society Reviews, vol. 49, no. 21, pp. 7671–7709, Jan. 2020, doi: 10.1039/d0cs00304b.