Drug Release Characteristics of Modified PHEMA Hydrogel Containing Tethered PEG Sulfonate

Conclusions The modified PHEMA hydrogel containing sulfonated PEG tether was prepared and the drug incorporation and release behavior was investigated to elucidate the effect of swelling and the ionic sulfonate groups on the PEG chain end. By using the model drugs including biphenyl acetic acid (BPAA), cationic methylene blue (MB), and anionic methyl orange (MO), it was found that the drug release behavior was significantly influenced by the electrostatic interactions between drug molecules and the inner surface nature of gel matrix to modulate the capacity and release rate of drugs.