Development of tyrosinase based biosensor and its application for monitoring of bioremediation of phenol and phenolic compounds

A tyrosinase-modified solid composite biosensor has been developed, and its application for the determination of phenol and related compounds in environmental samples was studied. The composite transducer for amperometric biosensor was based on graphite powder modified with tyrosinase and 2-hexadecanol used as a solid binding matrix. The response of a biosensor modified with 4% of tyrosinase was linear up to 2.5 mu M, the sensitivity was 0.0225 mu A/mu M, and the detection limit 0.2 mu M. Various parameters influencing biosensor performance have been also studied: working potential, buffer concentration, pH, and response with other compounds. The sensitivity of biosensor without surface renewal decreased to 20% of the initial value after 1 month. The sensitivity is restored after surface renewing. The biosensor was tested in laboratory-scale experiments for monitoring of phenol bioremediation in water and soil. The biosensor was also tested for analysis of other phenolic wastes: leachate from leather processing containing chlorophenols and waste from oil processing containing polyphenols.