| Abstract: | Provided herein are single domain antibodies (sdAbs) configured for passing the blood brain barrier in a human or mammal brain. Methods of using such sdAbs are also described herein, such as methods of binding to brain cells, binding with and transporting other sdAbs with beneficial functionalities, binding to and transporting biochemical or pharmaceutical species with beneficial functionalities, and treating, diagnosing, or prophylactically treating a disease, malignancy, or condition. |