Catechol Biosensor Based on Immobilizing Laccase to Modified Core-shell Magnetic Nanoparticles Supported on Carbon Paste Electrode
基于磁性纳米粒子固定技术的漆酶传感器用于垃圾堆肥中邻苯二酚的检测

A catechol biosensor was developed and used to analyze compost extracts based on the immobilization of laccase on the surface of modified magnetic core-shall (Fe3O4-SiO2) nanoparticles. Laccase was convalently immobilized on the magnetic nanoparticles by glutaraldehyde, which were modified with amino groups on its surface. The resulting magnetic bio-nanoparticles were attached to the surface of carbon paste electrode with the help of a permanent magnet to determine catechol. The immobilization matrix provided a good microenvironment for retaining the bioactivity of laccase. The linear range for catechol determination was 7.5×10-7-2.75×10-4 mol/L, with a detection limit of 7.5×10-7 mol/L. The detection current reached 95% of the steady-state current within about 70 s. Catechol concentration in compost extracts were determined by laccase biosensor and HPLC, with approximately the same result.