Malvar O.,Institute of Microelectronics of Madrid IMM CSIC |
Ramos D.,Institute of Microelectronics of Madrid IMM CSIC |
Martinez C.,Institute of Microelectronics of Madrid IMM CSIC |
Kosaka P.,Institute of Microelectronics of Madrid IMM CSIC |
And 2 more authors.
Sensors (Switzerland) | Year: 2015
We report the use of commercially available glass microcapillaries as micromechanical resonators for real-time monitoring of the mass density of a liquid that flows through the capillary. The vibration of a suspended region of the microcapillary is optically detected by measuring the forward scattering of a laser beam. The resonance frequency of the liquid filled microcapillary is measured for liquid binary mixtures of ethanol in water, glycerol in water and Triton in ethanol. The method achieves a detection limit in an air environment of 50 μg/mL that is only five times higher than that obtained with state-of-the-art suspended microchannel resonators encapsulated in vacuum. The method opens the door to novel advances for miniaturized total analysis systems based on microcapillaries with the add-on of mechanical transduction for sensing the rheological properties of the analyzed fluids without the need for vacuum encapsulation of the resonators. © 2015 by the authors; licensee MDPI, Basel, Switzerland.