Thermally killed cells of complex microbial culture for biosensor measurement of BOD of wastewater

Abstract

Multi-species microbial cells of a commercial preparation of activated sludge were thermally killed by exposure to 300 °C for 1.75 min. Their BOD biosensing efficacy compared well with the corresponding living cells. They incurred slightly longer response and recovery times for pseudo steady-state BOD measurement but their sensitivity, stability and reproducibility were better than their corresponding living cells. Unlike the living cell biosensors, the thermally killed cell biosensors require no nutrients or low temperature storage conditions. More importantly they satisfy the essential requirement for the commercialisation of biosensor with their suitability for bulk preparation of the biofilms which can be conveniently stored until they are required for their installation and fabrication of the biosensors. © 2004 Elsevier B.V. All rights reserved.