We seek to develop hydrogel formulations for injectable controlled drug delivery from Pluronics to enhance patient compliance, decrease side effects and reduce dose and frequency. Pharmaceutically, these systems are attractive due to their unique sol-gel phase transition in the body, biocompatibility and safety and are injected as solutions before transforming to gel matrices at body temperature. Pluronic F-127 is a block copolymer (PEO-PPO-PEO) that gels at low concentrations and can be tuned using other excipients. These experiments will quantify, for the first time, structural changes of concentrated F-127 systems mixed with a control drug and additives under controlled temperature after combined shear and extensional flow as experienced during real bodily injection. Correlating these changes to drug release will allow us to optimise novel injectable pharmaceutical formulations.