DNA Drag Race (image) Brown University Share Print E-Mail Caption Fluorescent stained DNA molecules make their way across of fluid channel pocked with tiny pits. The pits act as 'entropic barriers.' Credit Stein lab / Brown University Usage Restrictions None Share Print E-Mail 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.