A Mercury-Free, Piezo-Assisted Micro-Cutter for Embryo Biopsy

In embryo biopsy procedures such as preimplantation genetic diagnosis (PGD), piezo-assisted micro-cutters have been recently employed to facilitate the perforation of embryo zona pellucida. In such procedures, embedded mercury in the cutting micropipette is conventionally utilized to suppress excessive vibration of the micropipette tip during perforation. However, contaminated mercury is a toxic material that can substantially harm embryo viability and its subsequent development and, eventually diminishes the success rate of the biopsy procedure. The primary focus of this research proposal is devoted to design, model, and test of a mercury-free, piezo-assisted micro-cutter for embryo biopsy. The role of embedded mercury will be first numerically identified by developing a three-dimensional, nonlinear model of a micropipette driven longitudinally by a piezoelectric actuator based on Kane s method. Furthermore, the driving frequency and amplitude along with the micropipette surrounding fluid effects on the perforation quality will be investigated. The proposed, mercury-free micro-cutter will be manufactured, experimentally tested, and validated against the developed models.