Gold Nanoparticles Pulling on DNA (image) North Carolina State University Caption Because gold nanoparticles have a slight positive charge from the ligands, and DNA is always negatively charged, the DNA and nanoparticles are pulled together into complex packages. Credit Yaroslava Yingling, North Carolina State University Usage Restrictions Image credit must be given. 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.