高灵敏度二氧化硫光纤传感器的研究

Studies on a Fiber Optical Sensor for Sulfur Dioxide with a High Sensitivity

以奎宁为荧光试剂，通过改变传感液膜的组成及采用非稳态测量法，研制成功高灵敏度的二氧化硫光纤传感器，该传感器的线性响应范围为３．１×１０－７～７．８×１０－５ｍｏｌ／Ｌ，检测限达１．６×１０－７ｍｏｌ／Ｌ．研究了内充液中ＮａＨＳＯ３浓度、内充液层厚度对该光纤传感器动态响应信号的影响，用该传感器测定了葡萄酒中游离二氧化硫的含量。

The present paper decribes a fiber optical sensor with a high sensitivity to determine sulfur dioxide. In order to improve the sensitivity, a non steady state approach was adopted and the sensor response was recorded after the reaction being proceeded for 1 or 2 min. Effects of NaHSO 3 concentration and thickness of sensing layer of liquid on the sensor response were investigated. A good linearity in a wide concentration range of sulfur dioxide, 3.1×10 -7 ￣7.8×10 -5 mol/L, was displayed. The detection limit was 1.6×10 -7 mol/L . Using the sensor to determine the amounts of SO 2 in the wine, the results were in good agreement with the results obtained by the standard method.