 PERGAMON Mechatronics 7 "0887# 450Ð472 9846Ð3047:87 ,*see front matter Þ 0887 Elsevier Science Ltd[ All rights reserved[ PII]S9846Ð3047"87#99997Ð6 A positive displacement micropump for microdialysis James Cunneen a \ Yu!Cheng Lin c \ Simone Cara.ni b \ James G[ Boyd b \ Peter J[ Hesketh a\ \ Susan M[ Lunte d \ George S[ Wilson d a Microfabrication Applications Laboratory\ Department of Electrical En`ineerin` and Computer Science b Department of Mechanical En`ineerin`\ University of Illinois at Chica`o\ Chica`o\ IL 59596\ U[S[A[ c Department of En`ineerin` Science\ National Chen` Kun` University\ Tainan\ Taiwan\ ROC d Department of Chemistry and Pharmaceutical Chemistry\ University of Kansas\ Lawrence\ KS 55936\ U[S[A[ Received 1 December 0886^ accepted 3 February 0887 Abstract Miniature ~uid pumps\ measuring 04×3×0 mm\ have been microfabricated with silicon\ glass\ and polyimide[ Pumps have been tested with deionized water and 09) glycerol solutions as the working solutions[ The pumps have been operated with a pneumatic drive or a pie! zoelectric drive[ Flow rates from 9[0 to 009 ml min −0 have been achieved[ The maximum pressure generated by the pumps was 45 cm of water[ Pumps have been operated with a dialysis probe and with a microchannel load[ The pump lifetime is limited by the degradation in the performance of the polyimide components in the pump[ The power consumption was less than 0 mW at a drive frequency of 09 Hz[ Þ 0887 Elsevier Science Ltd[ All rights reserved[ 0[ Introduction Microfabrication technology has been successful in producing a wide range of miniature sensors ð0\ 1Ł\ micro!electro!mechanical devices "MEMS# ð2\ 3Ł\ and\ more recently\ micro!chemical analysis systems ð4\ 5Ł and microsystems ð6\ 7Ł[ Microsystems here are de_ned as miniature ~uid handling systems which use ~uids as the primary  Corresponding author[ E!mail] peterÝeecs[uic[edu