Sensing property of Ga2O3-based extended-gate field-effect transistors for a living cell viability sensor

• Published in: Sensors and actuators. A. Physical. Vol. 349; p. 114071
• Main Authors: Chou, Hsin-Yu, Chiang, Jung-Lung, Yu, Chang-Tze Ricky, Chen, Jo-Mei Maureen, Wuu, Dong-Sing
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.01.2023
• Subjects: EGFET; Ga2O3 nanorods; Glucose; Living cell viability sensor; PH sensing; PH sensing; Glucose; Living cell viability sensor; Ga2O3 nanorods; EGFET
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2022.114071

In this study, gallium oxide (Ga2O3) nanorods were deposited onto an indium tin oxide (ITO) glass substrate to develop a real-time living cell viability sensor. Ga2O3 nanorods had characteristics of cell population sensing based on cellular metabolism to detect cell viability. The pH sensing characteristics of Ga2O3-based extended-gate field-effect transistors (EGFETs) with and without the annealing process were measured from pH 1–11. Three different sensor heads, ITO/glass, GaOOH/ITO/glass, and Ga2O3/ITO/glass, were produced as EGFETs and immersed into a pH standard buffer and high-glucose Dulbecco’s modified Eagle’s medium (DMEM) to investigate hydrogen ion sensing. Results showed that the Ga2O3/ITO/glass probe had the best hydrogen ion sensing sensitivity and stability in different sample buffers. In contrast, GaOOH/ITO/glass had instability and lower sensitivity due to interference with other components in the medium. The drift characteristic of sensors was analyzed to detect long-term stability. The Ga2O3/ITO/glass probe showed lower drift properties, which can potentially monitor the DMEM situation in real-time for a long-term period. During in vitro detection, the Ga2O3/ITO/glass probe revealed a 70 μA/cells change in IDS-VDS analysis and a 10 μV/cells change in IDS-VGS analysis, which was superior linearly dependent within 10,000 cells. The biocompatibility of the Ga2O3/ITO/glass probe was also detected by 3-(4,5-dimethylthiazol-2-yl)− 2,5-diphenyltetrazolium bromide assay and showed no cytotoxicity. Overall, the Ga2O3/ITO/glass EGFET sensor has potential applications as a living cell viability device in microenvironmental studies in the future. [Display omitted] •This study creates a device that can be used to monitor changes in living cell viability.•Ga2O3/ITO/glass was connected to 2N7000 MOSFET to synthesize a detection device.•The annealed Ga2O3 film has higher stability and better hydrogen ion concentration response.