Automated mouse embryo injection moves toward practical use

Taking a different architecture than manual operation and existing microrobotic systems, this paper presents the first automated system that employs novel microfabricated cell holding devices and vision-position based control of multiple motion control devices to achieve easy sample immobilization, rapid cell orientation, and fast injection of mouse embryos. The system requires minimal human involvement through a maximum of three computer mouse clicking per mouse embryo, is human operator skill independent, and is immune from fatigue. While no robotic systems have provided performance close to manual operation, according to the preliminary experimental results (n = 90) from this study, this microrobotic system demonstrated: (i) an injection speed of 9 embryos/min vs. 2 embryos/min in typical manual operation, (ii) a success rate of 98.9%, a higher rate than the best success rate (90%) achieved by proficient injection technicians with over 10 years´ experience, and (iii) a high survival rate of 82.1%, a rate comparable with the best survival rate (~80%) achieved by proficient injection technicians. Further improvement of the automated system will change the way of how mouse embryos are injected and promise its practical use in biology laboratories and mouse facilities.