The Role of MEMS in In-Vitro-Fertilization

The assisted reproduction has been considered a viable solution for the infertility of humankind for more than four decades. In-Vitro-Fertilization (IVF) is one of the most successful assisted reproduction techniques, where the reproductive cell of the female partner is fertilized outside of her body. Initially, the IVF process has been conducted manually by an experienced embryologist. However, even with a highly experienced individual, the operation had extremely lower success rates due to the limited control in environmental conditions and the requirement of precise movements. Therefore, to address this technological deficit, the feasibility of the mechatronics devices for IVF procedures has been investigated. Among the different mechatronics concepts, micro-electromechanical system (MEMS) technologies have been gradually attracted to the IVF process and improved its capabilities. The purpose of this paper is to present a brief overview of the role of MEMS technologies in IVF. The article classifies the MEMS technologies in IVF based on their application in order to emphasize its contribution. In addition, the article extensively discusses the state-of-the-art mechatronic techniques utilized in Intracytoplasmic Sperm Injection (ICSI), one of the most popular techniques used in IVF. This review article expects to become extremely beneficial for the engineering researchers new to this field who seek critical information on IVF in simple terms with highlights on the possible advancements and challenges that may emerge in the future

Ultrasonic actuation of a fine-needle improves biopsy yield

Despite the ubiquitous use over the past 150 years, the functions of the current medical needle are facilitated only by mechanical shear and cutting by the needle tip, i.e. the lancet. In this study, we demonstrate how nonlinear ultrasonics (NLU) extends the functionality of the medical needle far beyond its present capability. The NLU actions were found to be localized to the proximity of the needle tip, the SonoLancet, but the effects extend to several millimeters from the physical needle boundary. The observed nonlinear phenomena, transient cavitation, fluid streams, translation of micro- and nanoparticles and atomization, were quantitatively characterized. In the fine-needle biopsy application, the SonoLancet contributed to obtaining tissue cores with an increase in tissue yield by 3-6x in different tissue types compared to conventional needle biopsy technique using the same 21G needle. In conclusion, the SonoLancet could be of interest to several other medical applications, including drug or gene delivery, cell modulation, and minimally invasive surgical procedures.Peer reviewe

A Flexure-guided Piezo Drill for Penetrating the Zona Pellucida of Mammalian Oocytes

Opening of the outer membrane, zona pellucida, of an oocyte is an important procedure in clinical in vitro fertilization. Piezo drills use piezo-actuated vibrations on a glass micropipette to effectively penetrate the zona pellucida. However, this technology has not seen wide-spread clinical adoption due to the damage caused to the oocyte by large lateral vibration of the micropipette tip induced by the axial pulses. This thesis describes a new piezo drill device which uses a flexure guidance mechanism to control the micropipetteâ s motion during zona pellucida penetration. By designing the system with careful consideration of the micropipetteâ s dynamics, the in-air lateral vibration of the micropipette tip is reduced to less than 500 nm, a 20 times decrease of that reported in current literature. Its effectiveness in zona pellucida penetration was quantitatively evaluated using mouse oocytes which are notorious for being the most difficult to penetrate compared to other mammalian oocytes.M.A.S.2018-12-06 00:00:0