Dielectrophoresis

The increasing trend toward quality assurance programs and hazard analysis, consumer demand for a wide variety of wholesome foods, and legislative pressures (e.g., the U.K. Food Safety Act) have increased the need for more rapid microbiological analyses. Although hazard analysis and critical control point (HAACP) programs have reduced the emphasis on end product testing, microbiological analyses have a particular role in environmental monitoring, validation, verification, and to ensure compliance to legislative specifications (e.g., EC (European Community) microbiological criteria (1 ). Although extremely sensitive and not particularly capital intensive (except where automation is required), the classical, cultural-based microbiological techniques are time consuming, labor-intensive, and give results that are only of retrospective value. For example, a typical pathogen test (e.g., Salmonella ) can include pre-enrichment, selective enrichment, selective plating, and confirmation can take up to 7 d to complete.