Integrated Dielectrophoretic Chip for Diagnosing Microbial Infections of Blood

MEMS offer many advantages over traditional diagnostic technologies. For the diagnosis of sepsis, or a microbial infection of the blood, MEMS may reduce or eliminate the time-consuming microbe culturing requiring days to weeks in traditional approaches. The challenge posed by sepsis diagnosis is the relatively small microbe concentration, tens to thousands per milliliter of blood containing several millions of various types of blood cells. To overcome this challenge, we propose a three stage integrated device for microbe sorting, trapping, and identification. Using dielectrophoretic forces, the microbes are sorted from blood cells and preconcentrated on a trap facilitated by surface-bound antibodies. After preconcentration, the trapped microbes are then lysed to produce a concentrated analyte for elucidating an electrical impedance signal in the subsequent genomic identification module. The necessary sample pretreatment and device sensitivity are explored. This integrated device illustrates the potential power of leveraging MEMS technology for disease diagnosis.