This study identifies a simple process and a hand held device to quickly conduct an analysis, under field conditions, for detection of pathogens. Hand held devices for rapid detection of pathogens have been proposed to be used by first responders. A magnetic sandwich immunoassay is developed for rapid isolation and detection of targeted pathogen. Escherichia coli BL21 Star (DE3) pLysS is used as a model in this study. The magnetic immunoassay takes advantage of the multiple epitopes that are found on the target. On one epitope a magnetic particle is attached. On another epitope a glucose molecule is attached. Glucometers have been designed with suitable accuracy to detect small amounts of glucose through the oxidation of glucose to gluconic acid at the site of platinum electrode. The sandwich magnetic assay that contains the glucose label can be easily correlated to the concentration of the Escherichia coli BL21 Star (DE3) pLysS.