Synthesis and Characterization of PolyHEMA Microparticels for Drug Release

Poly(HEMA-co-EGDMA) microparticles were synthesized by using suspension polymerization at different ratios of the monomer, 2-hydroxy ethyl methacrylate (HEMA) and the crosslinker, ethylene glycol dimethacrylate (EGDMA) at 70 °C for 3 hours with stirring at 350 rpm. The redox couple ammonium persulfate (APS) and N,N,N',N-tetramethylene diamine (TEMED) was used as the initiator. Magnesium oxide (MgO) was used as the stabilizer. Ratios of monomer and crosslinkers were altered to synthesise different microbeads of poly(HEMA-co-EGDMA) with different crosslinking ratios. The swelling behaviour of the microparticles was analysed in three different buffer solutions: acetate buffer at pH 2.0, phosphate buffer at pH 7.4 and pH 11 at 37 °C. In addition, loading of flurbiprofen and methylene blue into the microparticles and their release characteristics were investigated. Drug loaded and unloaded samples were analysed by FT-IR spectroscopy and scanning electron microscopy (SEM). Keywords: Poly(HEMA-co-EGDMA), Microbead, Copolymer, Flurbiprofen, Methylene Blue, Controlled Release, HEMA, EGDMA.