Figure 1.

Fe²⁺ first becomes oxidized by losing an electron and turns into Fe+3 (ferric iron). Ferric iron will then bind to transferrin, which subsequently binds to the transferrin receptor. Binding to the TfR allows for iron to enter the brain through the BBB.² Adapted with permission from ref (2). Copyright 2018 Brian Lindshield, Kansas State University. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.