title: Monitoring oxygen consumption of single mouse embryos using an integrated electrochemical microdevice.
abstract: Oxygen consumption (respiration activity) has been found to be the most remarkable criterion for determining the viability of an embryo produced in vitro. In this study, we propose an accurate, simple, and user-friendly device for measurement of the oxygen consumption of single mammalian embryos. An integrated electrode array was fabricated to determine the oxygen consumption of a single embryo, including the blastocyst stage, which has an inhomogeneous oxygen consumption rate, using a single measurement procedure. A single mouse embryo was positioned in a microwell at the center of an integrated electrode array, using a mouthpiece pipette, and immobilized by a cylindrical micropit with good reproducibility. The oxygen consumption of two-cell, morula, and blastocyst stages was measured amperometrically using the device. The recorded current profile was corrected to take into consideration transient background current during the measurement. A calculation method for oxygen consumption based on spherical diffusion centered on the defined point of the device was developed. This procedure is quite simple because it is not necessary to estimate the radius of the embryo being measured. The calculated values of oxygen consumption for two-cell, morula, and blastocyst stages were 1.36±0.33×10(-15) mol s(-1), 1.38±0.58×10(-15) mol s(-1), and 3.44±2.07×10(-15) mol s(-1), respectively. The increasing pattern of oxygen consumption from morula to blastocyst agreed well with measurements obtained using conventional scanning electrochemical microscopy (SECM).
authors.affiliation: Graduate School of Environmental Studies, Tohoku University, Sendai 980-8579, Japan.
authors.forename: Yasumoto
authors.initials: Y
authors.lastname: Date
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Takano
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Shiku
authors.forename: Kosuke
authors.initials: K
authors.lastname: Ino
authors.forename: Takahiro
authors.initials: T
authors.lastname: Ito-Sasaki
authors.forename: Masaki
authors.initials: M
authors.lastname: Yokoo
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Abe
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Matsue
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation*; D017076:Computer-Aided Design; D003217:Conductometry / Q000295:instrumentation*; D004622:Embryo, Mammalian / Q000502:physiology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005323:Fetal Monitoring / Q000295:instrumentation*; D051379:Mice; D008904:Miniaturization; D010092:Oximetry / Q000295:instrumentation*; D010101:Oxygen Consumption / Q000502:physiology*; D011296:Prenatal Diagnosis / Q000295:instrumentation*; D018511:Systems Integration