Evaluation of the Basic Designs of a Micro Device that Provides Vibrational Stimulation to Cells

It is known that the cells responds to external mechanical stimulations. Although the effectiveness of vibrational stimulation for the osteoanagenesis has been reported, the clarification of detailed mechanism for this phenomenon is insufficient. In this study, a micro device has been developed to evaluate the cell dynamics and responses to vibrations. The micro device has an array of moving micro stages which have transparent 5 µm thick thin film to enable them to observe the cell responses to vibrational stimulations by using an optical microscope. The moving micro stages are moved with a needle actuated by piezo actuator. Microfabrication processes, such as conventional photolithography, lift-off, and sacrificial layer etching, were used to fabricate the micro device. We designed two types of concepts for supporting and vibrating moving micro stages. Prototypes were fabricated and evaluated under vibrational conditions. Proposed design with the moving micro stages vibrating perpendicular to the beams generated simple linear oscillation without rotation. It was verified that the fabricated micro stage could be vibrated at the acceleration amplitude of 0.1 and 0.2 G with frequency 15, 45, and 90 Hz.