ABSTRACT
Superporous poly(2-hydroxyethyl methacrylate) (PHEMA) supports with pore size from tens to hundreds micrometers were prepared by radical polymerization of 2-hydroxyethyl methacrylate (HEMA) with 2 wt% ethylene dimethacrylate (EDMA) with the aim to obtain a support for cell cultivation. Superpores were created by the salt leaching technique using NaCl or (NH4)2SO4 as a porogen. Addition of liquid porogen (cyclohexanol/dodecan-1-ol (DOH) (CyOH/DOH) = 9/1 w/w) to the polymerization mixture did not considerably affect formation of meso-and macropores. The prepared scaffolds were characterized by several methods including water and CXR by centrifugation, water regain by suction, scanning electron microscopy (SEM), mercury porosimetry, and dynamic desorption of nitrogen. High vacuum scanning electron microscopy (HVSEM) confirmed permeability of hydrogels to 8 µm microspheres, whereas low vacuum scanning electron microscopy (LVSEM) at cryo-conditions showed the undeformed structure of the frozen hydrogels. Interconnection of pores in the PHEMA scaffolds was proved. Water regain determined by centrifugation method did not include volume of large superpores (imprints of porogen crystals), in contrast to water regain by suction method. The porosities of the constructs ranging from 81 to 91% were proportional to the volume of porogen in the feed.
