Serum level

Serum is the clear liquid that can be separated from clotted blood. Serum is the blood plasma not including the Fibrinogens. It includes:

• All proteins not used in blood clotting (Coagulation)
• and all the electrolytes, antibodies, antigens, hormones, and any exogenous substances (e.g., drugs and microorganisms).

In other words, Serum is:

• neither a blood cell (serum does not contain white or red blood cells)
• nor a clotting factor;