writer：Xiaoying Yang, Liting Chen, Bo Huang, Feng Bai, Xinlin Yang*
keywords：pH-sensitive polymer microsphere; Drug delivery
source：期刊
specific source：Polymer, 50 (15), 3556-3563 (2009). DOI: 10.1016/j.polymer.2009.06-027
Issue time：2009年
The pH-sensitive hollow poly(N,N0-methylene bisacrylamide-co-methacrylic acid) (P(MBAAm-co-MAA)) microspheres were prepared by a two-stage distillation precipitation polymerization to afford a core–shell poly(methacrylic acid)/poly(N,N0-methylene bisacrylamide-co-methacrylic acid) (PMAA/(P(MBAAm-co-MAA))) microsphere with subsequent removal of poly(methacrylic acid) (PMAA) core. PMAA/P(MBAAm-co-MAA) core–shell microspheres were synthesized by the second-stage copolymerization of N,N0-methylene bisacrylamide (MBAAm) as crosslinker and the functional methacrylic acid (MAA) comonomer in acetonitrile with 2,20-azobisisobutyronitrile (AIBN) as initiator. The pH-responsive properties of hollow P(MBAAm-co-MAA) microspheres were investigated by dynamic laser scattering (DLS). The loading and controlled-release behavior of the drug for hollow P(MBAAm-co-MAA) microspheres was strongly dependent on the pH values with doxorubicin hydrochloride (DXR) as a model molecule. The core–shell and hollow polymer microspheres were characterized by transmission electron microscopy (TEM), Fourier-transform infrared spectra (FT-IR), DLS and elemental analysis.