A Fully-Integrated MEMS Preconcentrator for Rapid Gas Sampling

In this paper, we present a new type of MEMS gaseous species preconcentrator (μPC) that has been fabricated and tested as a front end for a flame ionization detector (FID). A one microliter μPC filled with microposts is integrated with microvalves (response time <50 μs) and a resistive microheater (ramping to 200°C in 0.5 seconds). The integrated μPC can sample a cubic centimeter of gas in 0.2 second at 49 kPa, adsorb targeted species, heat and desorb, and inject concentrated gaseous species with 50 microsecond pulses into separation columns and/or detectors. The unprecedented speed of this μPC is enabled by MEMS sizing and fabrication, allowing sniffing of phosphonates, toxic industrial chemicals (TICs), and other volatile compounds in seconds, rather than tens of minutes with conventional systems.