A multiplexed microfluidic impedance sensor for high throughput analysis of microparticles

A micromachined eight-channel Coulter counting device to achieve high throughput detection and counting of microparticles is reported. The design, fabrication and testing of the multichannel device is presented. The detection was implemented by measuring the resistance change of each individual microfluidic channel. The use of grounded isolation electrodes eliminates crosstalk among channels and thus allows simultaneous particle detection without crosstalk. Preliminary testing results using Juniperus Scopulorum (Rocky Mountain Juniper) pollen particles demonstrated the throughput of the device was significantly improved by simultaneously detecting particles through its parallel channels. This detection principle can be extended to a larger number of channels to further improve the detection throughput.