6 March 2009

Lab M’s innovative Captivate™ immunomagnetic separation (IMS) products accelerate bacterial isolation from food and environmental samples. The antibody-coated microscopic paramagnetic beads enhance a range of microbiological processes, reducing the need for traditional enrichment procedures. In addition to its ready-made Captivate™ range for E. coli serotypes and Salmonella isolation, Lab M provides a custom coating service.

Of particular importance in the isolation of Escherichia coli O157:H7 from meat and milk samples, Captivate can reduce the time required for total viable counts, delivering presumptive negative results for pathogens more rapidly. By combining the power of Captivate beads with Lab M’s chromogenic media, bacterial testing methods reach new levels of sensitivity and efficiency.

Captivate beads consist of a magnetite core enveloped by a ceramic zirconium oxide coating and have an average size of 2.5 µm. When mixed with a sample suspension and incubated, the antibody-coated beads “capture” the target bacteria by forming an antibody-antigen complex. These complexes are separated from any background organisms or interfering materials using a magnetic concentrator. The beads can then be plated to the appropriate selective media or used in other analyses following a straightforward wash procedure.