High Concentration Screenshot (VIDEO) University of Pennsylvania This video is under embargo. Please login to access this video. To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Caption Fluorescent markers attached to proteins speed past the researchers' cellphone camera. An innovative strobing system allows individual markers to be differentiated from their neighbors, allowing an accurate count, even in the ultra-low concentrations associated with hard-to-diagnose conditions. Credit University of Pennsylvania 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.