Microfluidic devices on glass for liquid mixtures concentration with coupled THz sensor

Microfluidic devices on glass for liquid mixtures concentration with coupled THz sensor ■

Salomao Moraes Da Silva, Salomao Moraes Da Silva, Salomao Moraes Da Silva, Johan Stiens, Johan Stiens, Johan Stiens, Stanislav Moshkalev, Stanislav Moshkalev, Stanislav Moshkalev, J.W. Swart, J.W. Swart, J.W. Swart, Roberto Lacerda de Orio, Roberto Lacerda de Orio, Roberto Lacerda de Orio, Vladimir Matvejev, Vladimir Matvejev, Vladimir Matvejev, Yuchen Zhang, Yuchen Zhang, Yuchen Zhang, Werner Vandermeiren, Werner Vandermeiren, Werner Vandermeiren, Cathleen De Tandt, Cathleen De Tandt, Cathleen De Tandt

Abstract ■

This paper reports on the performance of a sub-THz liquid sensor tool coupled to a microfluidic platform. Non-invasive, non-destructive and on-line measurements are demonstrated for the determination of ethanol concentration and for controlling via micromixer device. We have developed a label-free chemical sensing methodology coupling a sub-terahertz sensor technology in microfluidic devices fabricated on glass and polydimethylsiloxane. The concept of sensor in micromixer applications operating at 60 GHz for known etha-nol concentration ranging 0\% to 100\%, with a corresponding dynamic range of 2.79dB. The sensor allowed establishing the correlation between the mass flow rate and the ethanol concen-tration in the microfluidic system, where two-stream lines form the mixture in laminar flows, with Reynolds number < 13.54 and Peclet number > 25700. We demonstrated on-line sensing and linear control of ethanol concentration on demand with a small variation of 0.32\% (v/v) between measured and required ethanol concentration.