Biological systems depend on the precise movement of molecules. Nutrients must reach the cells that need them, therapeutics must cross biological barriers, and molecular cargo must arrive at the correct subcellular destination. When these transport systems fail, disease can emerge; when they are understood, they can be engineered for better diagnosis and treatment.​ We develop technologies to map where molecules go, how much reaches each cellular compartment, where transport fails, and how delivery systems can be redesigned for precision medicine.​