Facile fabrication of a TiO2 NW-based glucose sensor by direct ink writing

This paper presents the results of facile fabrication of a non-enzymatic glucose sensor by forming a sensing element based on TiO2 nanofilaments using direct ink writing (DIW). The glucose concentration in the solution was determined by changing the resistance of the TiO2 layer. Nanowires (NW) were obtained by hydrothermal synthesis in 10 M sodium alkali solution followed by heat treatment. The surface morphology of obtained samples was studied using scanning electron microscopy. The formation of a sensitive layer was carried out on a 3D printer with a specially designed print head from a suspension based on an aqueous solution of polyvinyl alcohol (PVA) followed by heat treatment in air. The suspension was analyzed for viscosity and contact angle. The sensitive layers were formed on a silicon substrate with a SiO2 surface oxide layer and gold contacts. Layers of TiO2 NW were formed between the contacts. The sensitivity of the sensor to glucose solutions of various concentrations was studied. As a result of the studies, the studied structures showed sensitivity to a glucose solution in the range from 1 to 100 mmol.