用于硝酸根浓度测量的反射式光纤SPR传感器

Reflective Fiber Optic SPR Sensor for Nitrate Concentration Measurement

提出一种反射式光纤表面等离子体共振(surface plasmon resonance, SPR)传感器用来测量硝酸根浓度.传感器采用反射式结构,并利用金膜来激发SPR.制备铜纳米粒子/碳纳米管(copper-nanoparticles/carbon-nanotube, Cu-NPs/CNT)膜作为硝酸根浓度测量的敏感膜.当溶液中硝酸根浓度发生变化时,吸附在CNT上的由铜催化产生的氨气的浓度也会随之改变,导致CNT折射率发生改变,从而使SPR谐振波谷发生移动,进而实现硝酸根浓度测量.实验结果显示该传感器在低浓度区间内的平均灵敏度达到了 14.14 nm/lg[ c /(mol · L^-1)].这种传感器易于封装,可以应用于远距离测量,将在生物化学参量测量方面有着潜在应用.

A reflective fiber optical sensor based on surface plasmon resonance(SPR)is proposed for measuring nitrate concentration. The reflective structure sensor is coated with gold film to excite SPR. A copper nanoparticles/carbon nanotube(Cu-NPs/CNT)film is prepared as a sensitive film for nitrate concentration measurement. When the concentration of nitrate changes, the concentration of ammonia catalyzed by copper adsorbed on the CNT also changes, thus causing the refractive index of the CNT to change. The change of the refractive index leads to the shift of SPR resonance dip, so that nitrate concentration can be measured. The experimental results show that the sensor had an average sensitivity of 14.14 nm/lg[ c /(mol · L^-1 )] in the low concentration range. This sensor is easy to package and can be used for long-distance measurement, and will have potential applications in biochemical parametric measurement.