Synthesis of 2-(diethylamino)ethyl methacrylate-based polymers Effect of crosslinking degree, porogen and solvent on the textural properties and protein adsorption performance

The effect of polymerization parameters such as crosslinking degree, solvent and porogen, on the surface area, pore structure, morphology and protein retention capacities of 2-(diethylamino)ethyl methacrylate-co-ethylene glycol dimethacrylate polymers obtained by photopolymerization was studied. Dimethylformamide (DMF) and acetonitrile (ACN) were used as solvents to obtain series A and B of polymers, respectively. Poly(ethylene glycol) (PEG) of 20 kDa and 1 kDa were used as polymeric porogens. The crosslinking degree and the porogen significantly affected the textural properties and the protein adsorption capacity of the polymers. Surface areas drastically decreased with increasing monomer/crosslinker ratio, due to the formation of polymeric matrixes that present wider pores, both in the meso and macropore range. Very high BSA retention capacities, up to 170 mg BSA/g, were achieved for the polymers with crosslinker contents of 70-60 mol%. The absence of porogen in the polymerization mixture or the presence of a solvent with low viscosity, favours the formation of narrower pores, which contribute to the surface area but are not accessible to large protein macromolecules. (C) 2010 Elsevier Ltd. All rights reserved.