TY - JOUR AU - AB - Sensors and Materials, Vol. 31, No. 12 (2019) 4103–4111 4103 MYU Tokyo S & M 7073 Xiaojun Han, Chao Li, and Daming Yong State Key Laboratory of Urban Water Resource and Environment, School of Chemical Engineering and Technology, Harbin Institute of Technology, 92 West Da-Zhi Street, Harbin 150001, China (Received September 30, 2019; accepted December 3, 2019) Keywords: amperometry, enzyme inhibition, heavy metals, microbial biosensor A whole-cell-based amperometric biosensor was fabricated using Escherichia coli cells immobilized on a glassy carbon electrode to detect mercury, cadmium, and zinc ions. E. coli cells were immobilized by the cross-linking method using bovine serum albumin (BSA) in glutaraldehyde (GA) vapor. The principle of the microbial electrode sensor is the inhibition of alkaline phosphatase (AP) enzyme activity by heavy metal ions. Therefore, by monitoring the oxidation current of the product generated by AP in a metal ion solution, its concentration was determined. The Michaelis–Menten constant (Km) for AP was evaluated to be 2.23 mmol/L. −11 The E. coli-based biosensor has detection limits of 5.58 × 10 mol/L for mercury ion, 5.10 × −10 −9 10 mol/L for cadmium ion, and 1.38 × 10 mol/L for zinc ion. The prepared biosensor can respond steadily for TI - Microbial Electrode Sensor for Heavy-metal Ions JF - Sensors and Materials DO - 10.18494/sam.2019.2645 DA - 2019-12-16 UR - https://www.deepdyve.com/lp/unpaywall/microbial-electrode-sensor-for-heavy-metal-ions-GCd0D08be4 DP - DeepDyve ER -