posted on 2019-06-04, 19:43authored byJingyun Jing, Bingyin Jiang, Fuxin Liang, Zhenzhong Yang
A bottlebrush-colloid
Janus nanoparticle (JNP) with a ball-and-stick
structure is reported. A single poly(4-vinyl benzyl chloride) (PVBC)
polymer chain was grafted onto the amine-capped Fe3O4@NH2 nanoparticle. pH-responsive 2-diethylaminoethyl
methacrylate (DEAEMA) and water-soluble oligo(ethylene glycol) methacrylate
(OEGMA) were sequentially grown from the PVBC backbone by ATRP, forming
a core–shell bottlebrush. The synthesized PVBC208-g-(PDEAEMA13-b-POEGMA8)-Fe3O4@NH2 JNPs are dispersible
in water and can be manipulated by a magnet. The Fe3O4 NPs with exposed −NH2 groups facilitate
accumulation at acidic sites. Hydrophobic dyes can be loaded within
the PDEAEMA at pH ≥ 7.5, while they are released at pH values
below 6.8. The composite JNPs are promising as a guided pH-responsive
delivery vector toward acidic solid tumors.