Document Type : Full Research Paper

Authors

1 PhD Candidate, Mechanical Engineering School, Iran University of Science & Technology

2 Assistant Professor, Mechanical Engineering School, Iran University of Science & Technology

3 Assistant Professor, Department of Embryology, Infertility and IVF Unit, Royan Institute

4 Assistant Professor, School of Mechanics, Aerospace and Civil Engineering, University of Manchester

10.22041/ijbme.2008.13455

Abstract

Recently, considerable biomedical attention has centered on the mechanical properties of living tissues at the single cell level. Stiffness is an important parameter in determining the physical properties of living tissues. Indeed, stiffness changes of the ovum as a single cell pose a unique challenge in determining the sequence of fertilization. The ovum's extracellular layer has been reported to be altered following fertilization in a process described as Zona reaction. In the present study, the Young's modulus of Zona Pellucida of the mouse ovum was evaluated using micropipette aspiration technique. By incorporating exact engineering principles into the cell mechanics and extract appropriate formula, the Young's modulus of metaphase II (MII) and pronuclear (PN) was measured. The experimental results clearly demonstrated that the mouse Zona Pellucida hardened following fertilization. This study involves the contents of Reproductive Biology and Mechanics, and opens up a new trail of thought for evaluating the quality of mammalian oocytes and embryos. 

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