Identifying the concentration of the ethanol by utilizing surface plasmon resonance technology

Abstract Ethanol is an important raw material in the chemical, pharmaceutical, and food industries. Due to the volatile nature of ethanol products, it is essential to monitor the concentration of ethanol in these products to prevent degradation caused by evaporation. This paper presents a sensor chip for detecting ethanol concentration. An aqueous solution is used as the ethanol solvent, and a surface plasmon resonance (SPR) sensor serves as the receiver. When ethanol interacts with the surface of the SPR sensor, the refractive index is modulated and then detected by the SPR sensor. Based on this principle, the sensor was fabricated and tested. Real-time experiments of identifying ethanol solutions with concentrations ranging from 0.5% to 4% demonstrated that the system exhibits good repeatability and durability. Furthermore, the device offers high detection sensitivity and low cost, making it suitable for widespread application in industrial production.