Suspended Microchannel resonators with integrated electrodes for thermal and electrical characterization of liquids

Suspended microchannel resonator (SMR) has been demonstrated as a versatile technique, allowing to measure mechanical, morphological or even optical properties of cells. However, physical properties of cells may substantially change depending on the chemical composition of the suspension medium. Therefore, it is essential developing novel multiparametric techniques able to provide a complete understanding of the biological samples by characterizing also the liquid in which the cells are suspended. In this work we both theoretically and experimentally introduce a novel electro-mechanical sensing technique using SMR devices with integrated electrodes that allow measuring different physicochemical properties of the liquid sample as thermal conductivity, dielectric constant, electrical conductivity or even concentration of ions. These measured liquid properties can ultimately be used to complement other typical SMR measurements, such as mass. Moreover, we show that this electro-mechanical approach can be also used as a transduction method and as a way of tuning the mechanical resonance frequency.