We have developed a technique that utilizes electrolysis-generated pneumatic pressure and centrifugal force to achieve simple and reliable control over liquids in the microfluidic system of a rotating circular disk (CD). Specifically, this new technique was demonstrated for the propulsion of liquids in an upstream direction, against the centrifugal acceleration field, with control over their flow rates (metering). We also developed a simple mathematical model to describe the metering of said liquids as a function of electrical current flowing through an electrolyte (for generating pneumatic pressure) and also as a function of the angular frequency of rotation of the CD. A good correlation between the model and experimental data was achieved. (C)2011 The Electrochemical Society. [DOI: 10.1149/2.028111jes] All rights reserved.