The protein fraction that migrates most rapidly toward the anode is which of the following?

The protein fraction that migrates most rapidly toward the anode is which of the following?

• A. Albumin
• B. Globulins
• C. Fibrinogen
• D. Transferrin

Answer: (A)

When proteins move in electrophoresis, their speed toward the anode depends on the net negative charge they carry at the buffer pH and their size—the greater the charge-to-mass ratio, the faster the migration. Albumin has the highest negative charge per unit mass among common serum proteins at alkaline pH and is relatively small, so it travels toward the anode most quickly. Larger proteins like globulins have lower charge density per mass and migrate more slowly. Fibrinogen is very large and, after clotting, not present in serum, so it would not reach the same rapid speed. Transferrin is negatively charged but larger than albumin, so its migration is slower than albumin’s. Therefore, albumin is the fraction that migrates most rapidly toward the anode.

When proteins move in electrophoresis, their speed toward the anode depends on the net negative charge they carry at the buffer pH and their size—the greater the charge-to-mass ratio, the faster the migration. Albumin has the highest negative charge per unit mass among common serum proteins at alkaline pH and is relatively small, so it travels toward the anode most quickly. Larger proteins like globulins have lower charge density per mass and migrate more slowly. Fibrinogen is very large and, after clotting, not present in serum, so it would not reach the same rapid speed. Transferrin is negatively charged but larger than albumin, so its migration is slower than albumin’s. Therefore, albumin is the fraction that migrates most rapidly toward the anode.