Extracellular antibodies are ideal research tools for cell-surface proteins.

No permeabilization/fixation because using extracellular antibodies allows you to work with live cells!

Benefits of live cell imaging:
✓ Monitor cell movement
✓ Study protein transport across the cell
✓ Investigate protein internalization

Cl^– channels are ubiquitously expressed transmembrane proteins that allow the diffusion of anions along their electrochemical gradient. Although the channels are equally (if not more) permeable to anions such as I^– or HCO₃^– than to Cl^–, they are known as Cl^– channels since this is the most abundant anion in physiological settings.