Sensitive non-invasive electrochemical sensing of glucose in saliva using amorphous SnOx decorated one-dimensional CuO nanorods rich in oxygen vacancy defects

• Published in: Applied surface science 2022-08, Vol.592, p.153349, Article 153349
• Main Authors: Wang, Dong, Zheng, Chunxiang, Li, Yuzeng, Han, Chenshuai, Fang, Hairui, Fang, Xuan, Zhao, Hongbin
• Format: Article
• Language: English
• Subjects: CuO-SnOx; Non-enzymatic glucose sensor; Non-invasive glucose monitoring; Oxygen vacancy defects; Saliva
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2022.153349

[Display omitted] •The addition of amorphous SnOx increases the oxygen vacancy defect of the composite.•Non-enzymatic glucose sensor based on amorphous SnOx decorated one-dimensional CuO nanorods was prepared.•The sensor has high sensitivity and selectivity and can respond well in actual saliva samples. The non-enzymatic glucose sensor with high sensitivity is significant for non-invasive glucose continuous monitoring in saliva. Herein, the composite with amorphous SnOx decorated one-dimensional CuO nanorods were prepared via the hydrothermal and sintering procedure. The sensitivity of sensor is 2303 μA mM−1 cm−2, and the detection range of sensor is 1 μM to 6000 μM. For interferences such as dopamine, lactic acid, ascorbic acid, and sodium chloride, the sensor has good selectivity. TPD confirmed that this composite with amorphous SnOx decorated CuO nanorods has oxygen vacancy defects. This enhanced performance should be attributed to the addition of amorphous SnOx, which induces more oxygen vacancy defects. This sensor with good electrochemical performance may be used for continuous detection of saliva with low glucose content. The sensor constructed by CuO-SnOx composite could detect the changes of glucose content in saliva before and after meals. Measuring glucose in saliva samples at different time intervals confirmed that it was closely related to the blood glucose level measured with a commercially available blood glucose meter. Oxygen-enriched vacancy defects induced by structure can improve the performance of sensors, which may provide some new ideas for the synthesis of high-performance sensor composite.