Snapshots (IMAGE) Proceedings of the National Academy of Sciences Caption Snapshots of uniform drops being generated by a microfluidic step emulsifier to encapsulate single circulating tumor cells. Credit PNAS Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.