Aggregate Structures of Lipids and their Biophysics

Water molecules are absent from the hydrophobic interior, but both the choline and the phosphate headgroups are fully solvated [41]. Similarly, the first hydration shell of the sulfate headgroup of SDS is formed rather by water molecules than by sodium ions. Because of hydration the charge density due to the lipid headgroups is overcompensated by the water dipoles, thereby reducing the transmembrane potential by 50-100 mV across the lipid water interface and resulting in a negative potential at the aqueous side [42]. 

C sodium taurodeoxylcholate (similar to CHAPS), D /i-octyl-/ -D-glucopyranoside and E lyso-dodecyl-phosphatidyl-glycerol. 

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