Investigation of refractive index dynamics during <i>in vitro</i> embryo development using off-axis digital holographic microscopy
George Dwapanyin, Darren J. X. Chow, Tiffany C. Y. Tan, Nicolás Dubost, Joséphine Morizet, Kylie R. Dunning, Kishan Dholakia
Abstract
fertilization clinic. Determining physical parameters of the embryo may offer key information for this purpose. Here, we demonstrate that digital holographic microscopy (DHM) can rapidly and non-invasively assess the refractive index of mouse embryos. Murine embryos were cultured in either low- or high-lipid containing media and digital holograms recorded at various stages of development. The phase of the recorded hologram was numerically retrieved, from which the refractive index of the embryo was calculated. We showed that DHM can detect spatio-temporal changes in refractive index during embryo development that are reflective of its lipid content. As accumulation of intracellular lipid is known to compromise embryo health, DHM may prove beneficial in developing an accurate, non-invasive, multimodal diagnostic.