Poly(2-hydroxyethyl methacrylate) (PHEMA) crosslinked with ethylene dimethacrylate (EDMA) or N,O-dimethacryloylhydroxylamine (DMHA) was obtained in the form of slabs by bulk radical polymerization. Two porosity-inducing methods were investigated. phase separation using a low-molecular-weight porogen and a salt-leaching technique using NaCl and saccharose.
Compared with the phase separation, the salt-leaching created open porous structures with voids of the size and shape of crystallites. To address its potentials in the context of stem cell therapies, undifferentiated mouse embryonic stem cells D3 (ES D3 cells) were seeded on the slabs and analyzed for the ability to grow on different types of non-degradable and/or degradable porous PHEMA hydrouels.
The cells were able to proliferate only on PHEMA crosslinked with EDMA or 2 wt% DMHA. In order to assess the effect of gelatin. which is routinely used for ES cell Cultures, PHEMA slabs were soaked in gelatin solutions and compared the number of cells on gelatin-treated and untreated slabs 4 days after cell seeding.
Surprisingly, the number of cells was only slightly higher oil gelatin-treated slabs.