No abstract

Well-defined PEGylated zwitterionic triblock copolymer, poly(ethylene glycol)-b-poly(methacrylic acid)-b-poly(2-aminoethyl methacrylate) (PEG-b-PMAA-b-PAEMA), was prepared from poly(ethylene glycol)-b-poly(tert-butyl meth acrylate)-b-poly(N-(tert-butoxycarbonyl) amino ethyl methacrylate)(PEG-b-PtBocMA-b-PtBoc AEMA) precursor synthesized via atom transer radical polymerization (ATRP) by successively polymerized tert-butyl methacrylate (tBocMA) and N-(tert-butoxycarbonyl) amionethyl methacrylate (tBocAEMA) monomers using a PEG-based macroinitiator followed by t-Boc group deprotection. The obtained triblock copolymer was confirmed by proton nuclear magnetic response (1 H NMR) and Gel Permeation Chromatography (GPC). The resultant PEG-b-PMAA-b-PAEMA copolymer bearing a large number of amine moieties will have potential applications as anti-cancer drug or DNA carriers.

A novel approach was developed to synthesize polymerizable vinyl group functionalized Fe 3 O 4 nanoparticles with high aqueous dispersion stability. Firstly, the Fe 3 O 4 nanoparticles were synthesized via chemical co-precipitation method. Then, azide-functional Fe 3 O 4 nanoparticles were obtained by a two-step chemical modification process. Finally, a quaternized 2-(Dimethylamino) ethyl methacrylate (QDMA) with alkyne moiety were directly reacted with azide-functional Fe 3 O 4 nanoparticles to obtain Fe 3 O 4 @QDMA nanoparticles. The Fe 3 O 4 @QDMA nanoparticles with a mean diameter 12.2 nm possess positive charges and can be well dispersed in water media for further preparation of particle-crosslinked magnetic nanocomposite hydrogels.