High frequency viscoelastic measurements of fluids based on microcantilever sensing: New modeling and experimental issues

In general, microrheology is carried out using active or passive particle-tracking techniques. In the present paper, a novel technique based on the out-of-plane bending vibrations of a microcantilever beam immersed into a liquid is proposed for microrheological property measurement. We propose to analytically link the damped beam motion with the rheological properties of the fluid in order to establish a dynamic rheogram which spans at least one decade of the kiloHertz frequency domain. The latest improvements in terms of both analytical modeling and experimental set-up are detailed, along with a complete explanation of the calculation method. Four rheograms of Newtonian and nonNewtonian liquids obtained from the frequency response of three immersed cantilevers of different geometries are presented.