An electrostatically actuated micro peristaltic pump is reported. The micro pump is entirely surface micromachined using a multilayer parylene technology. Taking advantage of the multilayer technology, the micro pump design enables the pumped fluid to be isolated from the electric field. Electrostatic actuation of the parylene membrane using both DC and AC voltages was demonstrated and applied to fluid pumping based on a 3-phase peristaltic sequence. A maximum flow rate of 1.7 nL min 21 and an estimated pumping pressure of 1.6 kPa were achieved at 20 Hz phase frequency. A dynamic analysis was also performed with a lumpedparameter model for the peristaltic pump. The analysis results allow a quantitative understanding of the peristaltic pumping operation, and correctly predict the trends exhibited by the experimental data. The small footprint of the micro pump is well suited for large-scale integration of microfluidics. Moreover, because the same platform technology has also been used to fabricate other devices (e.g. valves, electrospray ionization nozzles, filters and flow sensors), the integration of these different devices can potentially lead to versatile and functional micro total analysis systems (mTAS).

We present a MEMS sensor aiming to enable continuous monitoring of glucose levels in diabetes patients. The device features a magnetically-driven vibrating microcantilever, which is situated in a microchamber and separated from the environment by a semi-permeable membrane. Glucose sensing is based on affinity binding principles using a solution of dextran concanavalin-A (Con A) as the sensing fluid. The glucose concentration is determined by detecting viscosity changes induced by the binding of glucose to Con A through the measurement of the cantilever's vibration parameters. The device is capable of measuring physiologically relevant glucose concentrations from 0 to 25 mM with a resolution better than 0.025 mM and a phase sensitivity better than 0.4 • mM −1. The response of the sensor to glucose concentration changes has a time constant down to 4.27 min, and can be further improved with optimized device designs.

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