FIG. 2.

Photographs and schematics representing efforts made toward modification of the embryo culture microenvironment by confinement in microwells. A) Well-of-the-well (WoW) system, whereby curved microwells are produced in the bottom of a polystyrene Petri dish. Insert is micrograph of a blastocyst in a WoW microwell. B) Photograph of microwell imprints in PDMS contained in a Petri dish. C) These microwells can be constructed in a very precise manner as a cone with an opening of 180 μm and a bottom of approximately 10 μm. When embryos are place into these cone-shaped microwells, a microenvironment is formed. D) Schematic representing mechanism of surface modification that can be performed with ultraviolet-ozone activation of the surface and coating with a biomolecule of interest. This forms a uniform hydrogel surface that may have advantages in many types of cell culture [39]. Photograph of WoW kindly provided by Dr. Gabor Vajta.