A robotic microscope for 3D time-lapse imaging of early stage axolotl salamander embryos

Abstract

A robotic microscope was designed using a microcontroller to take time-lapse digital photographs of developing salamander embryos. The microcontroller operated three stepper motors to control three-axis movement accurately, and two six mega-pixel digital cameras to capture through-focus time-lapse digital pictures of six views of Ambystoma mexicanum embryos (axolotl, a salamander). The device is designed to take images every five minutes for 80 hours of early development, from fertilization to stage 20, when the neural tube closes to form the brain and spinal column. Techniques to enhance the embryo images were investigated including image fusion to get in-focus views from a stack of images.

In the early embryo surface epithelial cells differentiate to form neural tissue and external skin tissue. Observing the whole embryo surface at cellular level will give a better idea of the stress and strain each cell undergoes and what physical forces are involved in cell differentiation.