a	Molecular radius, Solute radius (m)
C	Concentration (g/m3)
$C_{A\underset{\_}{}pore}$	Concentration in a pore (mg/m3)
$C_{A\underset{\_}{}bulk}^{x=0}$	solute concentration in the pore at the inlet of the pore related with the bulk solute concentration (mg/m3)
DAB	Diffusion coefficient in a homogeneous fluid, usually used for water at 37 °C (m2/s)
$D_m$	Diffusion coefficient in membrane (m2/s)
Dpasma	Diffusion coefficient in plasma (m2/s)
$D_{pore}$	Diffusion coefficient in a pore (m2 / s)
K	Partition coefficient (−)
$\overline{L}$	Membrane thickness (m)
$N_{Ax}^{pore}$	Mass transfer flux in a pore (g/m2 s)
NA	Avogadoro’s number (6.02 × 1023 mol−1)
R	Universal gas constant
T	Absolute temperature (K)
r	Pore radius (m)
Greek letters
µ	viscosity (cP) (Pa s) (g/(cm s))
ρ	density (g/cm3)
τ	membrane tortuosity (−)
${\omega }_r$	Hindered diffusion parameter (−)
Subscripts/superscripts
A	Solute
$x=0$	Local value at $x=0$
$x=\overline{L}$	Local value at $x=\overline{L}$
plasma	Plasma
pore	Pore
bulk	Refers to the value in a bulk solution
x	Local value at position x (m)