A conductometric biosensor for biosecurity

The paper describes the development of a conductometric biosensor for detecting foodborne pathogens. The biosensor consists of two components: an immunosensor that is based on electrochemical sandwich immunoassay, and a reader for signal measurement. The architecture of the immunosensor utilizes a lateral flow system that allows the liquid sample to move from one pad to another. The biosensor provides a specific, sensitive, low volume, and near real-time detection mechanism. Results are presented to highlight the performance of the biosensor for enterohemorrhagic Escherichia coli O157:H7 and Salmonella spp., which are of concern to biosecurity. The lower limit of detection is approximately 7.9 x 10(1) colony forming units per milliliter within a 10-min process. The ability to change the specificity of the antibodies will enable the biosensor to be used as a detection device for other types of foodborne pathogens. (C) 2003 Elsevier Science B.V. All rights reserved.