A Fiber Optic Sensor for 2,4-dichlorophenol Analysis based on Optical Composite Oxygen-sensitive Film

Abstract

A novel fiber optic sensor based on optical composite oxygen-sensitive film was developed for determination of 2,4-dichlorophenol (DCP). The optical composite oxygen-sensitive film consists of tris(2,2′-bipyridyl) dichloro ruthenium(II) hexahydrate (Ru(bpy)3Cl2) as the fluorescence indicator and iron(III) tetrasulfophthalocyanine (Fe(III)PcTs) as bionic enzyme. A lock-in amplifier was used for detecting the lifetime of the composite oxygen-sensitive film by measuring the phase delay of the sensor head. The different variables affecting the sensor performance were evaluated and optimized. Under the optimal conditions (i e, pH 6.0, 25 °C, Fe(III)PcTs concentration of 5.0·10−5 mol/L), the linear detection range, detection limit and response time of the fiber optic sensor are 3.0×10−7–9.0×10−5 mol/L, 4.8×10−8 mol/L(S/N=3), and 220 s, respectively. The sensor displays high selectivity, good repeatability and stability, which have good potentials in analyzing DCP concentration in practical water samples.