A multi-sensor system for measuring bovine embryo metabolism

Abstract

This paper presents the development of a multi-sensor platform capable of simultaneous measurement of dissolved oxygen (DO) concentration, glucose and lactate concentrations in a micro-chamber for real-time evaluation of metabolic flux in bovine embryos. A micro-chamber containing all three sensors (DO, glucose, and lactate) was made to evaluate metabolic flux of single oocytes or embryos at different stages of development in ≤120 μL of respiration buffer. The ability of the sensor to detect a metabolic shift from oxidative phosphorylation (OXPHOS) to glycolysis was demonstrated in embryos by an ablation of oxygen consumption and an increase in lactate production following addition of oligomycin, an inhibitor of mitochondrial adenosine triphosphate (ATP) synthesis. An increased reliance upon glycolysis relative to OXPHOS was demonstrated in embryos as they developed from morula to hatched blastocysts by a progressive increase in the lactate/oxygen flux ratio, consistent with isolated metabolic assessments reported previously. These studies highlight the utility of a metabolic multi-sensor for integrative real-time monitoring of aerobic and anaerobic energy metabolism in bovine embryos, with potential applications in the study of metabolic processes in oocyte and early embryonic development.

Design of a multi-sensor platform for integrating extracellular acidification rate with multi-metabolite flux measurement for small biological samples

“…Additionally, electrochemical sensors can enable label-free, real-time intracellular and extracellular measurements without perturbing the system under investigation (Wang et al, 2012). There have been a number of reported studies that used electrochemical methods for measuring DO (Obeidat et al, 2016; Obeidat et al, 2018a), glucose (Pemberton et al, 2009; Obeidat et al, 2018b), lactate (Rawson et al, 2009; Obeidat et al, 2018b), and pH (McConnell et al, 1992; Liao et al, 1998).…”

“…This paper presents a multi-sensor platform to measure DO, glucose, lactate, and pH in real-time for small biological samples. Previously, we have reported a similar platform to characterize DO, glucose and lactate flux in bovine embryo (Obeidat et al, 2018b). In the work described herein, pH sensor was added to the platform to measure ECAR.…”

Bioengineered microenvironment to culture early embryos

“…Obeidat et al designed a multi‐sensor microfluidic system (Figure C), by monitoring the metabolites of the embryos in real time. The glycolytic metabolic demand was enhanced when the embryos were developing from morula to blastocysts . This shows the potential of using the platform in the embryo metabolism research.…”

“…To select well‐developed embryos, researchers have developed embryo characterization and evaluation platforms. The oxygen consumption, the utilization rate of glucose and other morphological parameters can be measured during in vitro embryo culture . To assess the viability of embryos, Wu et al designed a chip with a built‐in amperometric detector (Figure A), which can measure the oxygen consumption of a single embryo in situ.…”

“…Copyright 2007, Elsevier BV (B) A microfluidic detector was applied to continuously evaluate embryo metabolising: glucose, pyruvate and lactic acid . Copyright 2008, American Chemical Society (C) Three sensors in the microchamber were designed to measure the concentrations of dissolved oxygen, glucose and lactic acid in embryo metabolism . Copyright 2019, Elsevier BV (D) A light modulated microfluidic device was developed for multiple long‐term measurements of oxygen consumption and acid extrusion in embryo metabolism .…”