Microfluidic System for Biological Agent Detection

A MEMS-based microfluidic system capable of biological agent collection, treatment and detection is presented in this paper. The system incorporates microfluidic devices and an electrochemical DNA sensor to carry out airborne particle collection, sample preparation and identification with specificity. A silicon-nitride membrane filter was fabricated for airflow filtration, the design rule for pressure dissipation through μ-filter has been established through aerodynamic experiments and numerical simulations. An automated compact fluid handling system is built with a flexible configuration to accomplish sample preparation. Nucleic acid extraction has been successfully practiced with different protocols. By applying the synthesized oligonucleotide probes, the microfluidic system together with electrochemical DNA sensor has been characterized with cultured Escherichia coli. The test results show that positive identification of a specific biological agent can be aceved with the proposed microfluidic system