Respirocyte

Respirocytes are artificial red blood cells, which can take the place of our oxygen carrying cells and do a more efficient job in the process.

Still entirely theoretical, respirocytes measure 1 micrometre in diameter. Respirocytes mimic the action of the natural hemoglobin-filled red blood cells. The design of the spherical nanorobot is made up of 18 billion atoms arranged as a tiny pressure tank. The tank can be filled up with oxygen and carbon dioxide - making one complete transfer point at the lungs, and the reverse transfer at the body's tissues. Each respirocyte can store and transport 200 times more oxygen and carbon dioxide than our natural red blood cells. Filled with these respirocytes, an adult human could hold his/her breath underwater for four hours. That person could also sprint at top speed for at least 15 minutes without taking a breath.

- cited from respirocytes.info

Transhumanism
Can be discussed as part of a greater component of Transhumanism