| During past decades, interest in development of cell-based biosensors has increased considerably. In this study, two kinds of acoustic wave sensors are adopted as the cell-based biosensors to investigate the biomechanical and biological behaviors of cells, the quartz thickness shear mode (TSM) resonator and Love wave sensor. For the first part, the quartz TSM resonator is applied to detect the structural and mechanical properties of tendon stem/progenitor cells (TSCs), which are one kind of newly discovered adult cells in tendons, and the platelets from blood. Through the TSM resonator, the related viscoelastic properties of cells are extracted, which could indicate the state of cells in different physiological conditions. The TSM resonator sensor is utilized to characterize the aging-related viscoelasticity differences between the aging and young TSCs, and also to monitor the dynamic activation process of platelets. For the second part, a 36° YX-LiTaO 3 Love wave sensor with a parylene-C wave guiding layer is proposed as a cell-based biosensor. A theoretical model is derived, to describe the Love wave propagation in the wave guiding layer, the adherent cell layer, and penetration into the liquid medium. The Love wave sensor is used to monitor the adhesion process of cells. Compared with TSM resonator, the response of Love wave sensor to the cell adhesion is primarily induced by the formation of bonds between cells and the substrate. The numerical results indicate that the adherent cell layer of various storage or loss shear modulus in certain range can cause evident, characteristic variations in propagation velocity and propagation loss, revealing the potential of Love wave sensors in providing useful quantitative measures on cellular mechanical properties. In addition, a Love wave sensor with a phononic wave guiding layer is introduced for non-operation signal filtering and sensor sensitivity improvement. Both two kinds of acoustic wave sensors present their own advantages as the cell-based biosensors, indicating advisable techniques for investigating cell biology in general and certain physiological processes in particular. |
