Abstract
Complement activation is reduced by grafting polyethylene glycol (PEG) on the surface of conventional regenerated cellulose (RC) membranes. However, the solute permeability of PEG-grafted RC membranes may be lower than that of conventional RC membranes because of the presence of swollen-layers formed with PEG chains on the PEG-grafted RC membranes. The objective of the present study is to clarify the difference in membrane structure between conventional RC (AM-SD) and PEG-grafted RC (AM-PC) membranes, and to characterize three PEG-grafted cellulosic membranes (AM-PC(l), PC(m), PC(s)) with varying PEG chain lengths based on the tortuous capillary pore model using data on tritium-labeled water (HTO) permeability and filtration coefficient.
The pore radius and surface porosity of the AM-SD, PC (m) and PC (s) membranes were calculated to be 2.8nm and 35%, respectively. On the other hand, the pore radius and surface porosity of the PC(l) membrane grafted with the longest PEG chains were lower than those of the conventional RC membrane (SD). This indicates that the pores of the PC (l) membrane are partially covered with the PEG chains.
