Water permeation through the human cell membrane

A nanoscale calculation is performed for water permeation through the cell membrane in a human body, which is 7–8 nm thick and contains densely distributed nanopores with the radii ranging between 0.2 and 0.5 nm. The pressure drop and the critical power loss on a single nanopore for initiating the wall slippage are calculated. The wall slipping velocity is found to increase significantly with reduction of the pore radius and to increase linearly with an increase in the power loss on the pore. For no wall slippage, the water mass flow rate through the pore is significantly lower than the classical hydrodynamic flow theory calculation; however, it is much greater (by three to five orders of magnitude) than the classical hydrodynamic flow theory calculation in the case where the wall slippage occurs. This water flow enhancement is heavily dependent on the power loss on the pore.