Drug delivery polymer research. Researchers developing new stimuli sensitive polymers to deliver therapeutic agents directly to the cancer tumour site, minimizing the side effects caused by whole-body cancer treatments. These new polymers remain in a liquid form when dissolved in water, but form a solid gel under various stimuli such as body heat. This research is being carried out at Pacific Northwest National Laboratory (PNNL), Richland, Washington, USA. Image published in 2015.