Design of a bioelectronic tongue for glucose monitoring using zinc oxide nanofibers and graphene derivatives

Author(s)

Mercante, Luiza A. ^[1] ; Andre, Rafaela S. ^[2] ; Facure, Murilo H. M. ^{[3, 2]} ; Fugikawa-Santos, Lucas ^[4] ; Correa, Daniel S. ^{[3, 2]}

Affiliation

^[1] Fed Univ Bahia UFBA, Inst Chem, BR-40170280 Salvador, BA - Brazil

^[2] Embrapa Instrumentacao, Nanotechnol Natl Lab Agr LNNA, BR-13560970 Sao Carlos, SP - Brazil

^[3] Fed Univ Sao Carlos UFSCar, Ctr Exact Sci & Technol, Dept Chem, PPGQ, BR-13565905 Sao Carlos, SP - Brazil

^[4] Sao Paulo State Univ, Inst Geosci & Exact Sci, Phys Dept, UNESP, BR-13506900 Rio Claro, SP - Brazil

• Document type: Journal article
• Source: SENSORS AND ACTUATORS REPORTS; v. 3, NOV 2021.
• Web of Science Citations: 0

Abstract

Monitoring glucose levels is critical for diabetes management and might be a key step in the development of individualized treatment strategies. In this scenario, tracking salivary glucose has been recognized as a promising strategy due to its merits of ease sampling and non-invasive nature. In this paper, we report on the development of an electrical impedance-based biosensor array to distinguish glucose at different concentrations in saliva. The enzymatic biosensors were made of gold interdigitated electrodes coated with pristine electrospun zinc oxide nanofibers (NFZ) and NFZ combined with graphene-based nanomaterials (i.e., reduced graphene oxide - rGO and graphene quantum dots - GQDs), on which a layer of glucose oxidase (GOx) enzyme was adsorbed. Electrical impedance measurements indicate that the NFZ-GQDs@GOx and NFZ-rGO@GOx platforms presented good linear relationship with glucose concentration in the range of 0.1 to 6 mM. The highest sensitivity was reached for NFZ-rGO@GOx with a detection limit (LOD) of 14 mu M, while the LOD was 32 mu M for NFZ-GQDs@GOx. Both biosensors were also capable of detecting glucose in artificial saliva using aliquots of 10 mu L, with recovery between 87.3 and 106.8%. Furthermore, the three sensing units (NFZ@GOx, NFZ-rGO@GOx and NFZ-GQDs@GOx) were employed to build a bioelectronic tongue. Using Principal Component Analysis (PCA) technique to project the electrical impedance data of all sensing units allowed the discrimination of the different glucose concentrations and interferents. This study reveals the applicability of the developed bioelectronic tongue as noninvasive glucose sensors, which approach could also be pottentially adapted to detect other disease biomarkers present in saliva. (AU)

• FAPESP's process: 17/12174-4 - Development of hybrid polymer nanofibers for agricultural applications
• Grantee: Daniel Souza Corrêa
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/10582-8 - Production and characterization of graphene quantum dots and their application in chemical sensors
• Grantee: Murilo Henrique Moreira Facure
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 18/22214-6 - Towards a convergence of technologies: from sensing and biosensing to information visualization and machine learning for data analysis in clinical diagnosis
• Grantee: Osvaldo Novais de Oliveira Junior
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 16/23793-4 - Development of nanostructured sensor aiming the detection of volatile compounds for food quality indicators
• Grantee: Rafaela da Silveira Andre
• Support Opportunities: Scholarships in Brazil - Post-Doctoral