Nanoparticle for Anticancer Drug Delivery (IMAGE) Children's Hospital of Philadelphia Caption The nanoparticle is coated with a layer of polymer masking it from recognition and elimination by the immune system as it circulates in the body. When it reaches a tumor, it slowly releases a drug precursor. In the tumor, the specially designed precursor rapidly converts to a a potent anticancer drug. Credit Children's Hospital of Philadelphia 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.