Cationic nanogels based on diethylaminoethyl methacrylate

The effect of polymer composition and polymerization parameters such as comonomers, crosslinking ratio, and polymerization method, on the surface characteristics, surface chemistry, and swelling response of crosslinked 2-(diethylaminoethyl methacrylate) (DEAEM) and polyethylene glycol monoethyl ether monomethacrylate (PEGMMA) nanogels was studied. A novel inverse emulsion polymerization method was developed, which formed latex nanoparticles on the order of 100–400 nm. The properties of these nanogels were compared to microparticles synthesized via solution polymerization. The new polymerization method allowed the incorporation of PEG surface tethers of lengths 400 Da up to 2000 Da. Surface tethers successfully decreased the ζ-potential of these nanogels from 70 mV to 30 mV in acidic conditions and from −60 mV to 2 mV in basic media. Nanogels swelled from 100 nm in basic media to 800 nm in acidic media due to the protonation of the tertiary amine on DEAEM.