Rapid response electrowetting on dielectric of Ag-ZnO@STA nanocomposite coatings with antibacterial properties and the application for diabetes detection

Abstract

Electrowetting on dielectric (EWOD) has been developed dynamic blood glucose detection in many special areas of life. However, there are still disadvantages such as slow responsiveness, low sensitivity and poor reproducibility, even no bactericidal function. Herein, the superhydrophobic Ag-ZnO@STA/Zn composite device has been prepared by simple sol-gel and spin-coating techniques, in which Ag@STA nanoparticles are embedded into the interspaces of flower-like ZnO@STA nanosheets and formed the micro-nano hierarchical structure with large surface roughness. The EWOD performance of Ag-ZnO@STA/Zn device is optimized to achieve large contact angle (CA) modulation of 100° and superlow threshold voltage less than 1 V, which completely ensure the success application for the diabetes detection. The CA under voltage is used as a strategy for sensor response, the simulated physiological fluids are used as test liquid in EWOD, the prepared Ag-ZnO@STA/Zn device is endowed with high sensitivity detection ability to glucose with low concentration. More importantly, as the diabetes sensor, the Ag-ZnO@STA/Zn device has excellent anti-corrosion and bactericidal functions.