Poláková L, Raus V, Kostka L, Braunová A, Pilař J, Lobaz V, Pánek J, Sedláková Z
Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic , Heyrovsky Sq. 2, 162 06 Prague 6, Czech Republic.
Biomacromolecules. 2015 Sep 14;16(9):2726-34. doi: 10.1021/acs.biomac.5b00599. Epub 2015 Aug 14.
A series of model linear copolymers of 2-hydroxyethyl methacrylate (HEMA) and a sterically hindered amine derivative [N-(2,2,6,6-tetramethyl-piperidin-4-yl)methacrylamide (HAS)] were synthesized and characterized. Scavenging activities of the copolymers against reactive oxygen species (peroxyl and hydroxyl radicals) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals were determined. It was found that copolymers with medium HAS content (3.5-4.0 mol %) were better scavengers than copolymers with lower and higher HAS content and also than polyHEMA and polyHAS homopolymers and the HAS monomer. Importantly, these copolymers compared favorably even to established low-molecular weight antioxidant standards (BHA and dexpanthenol). Monomer reactivity ratios were determined, and the microstructure of the copolymers was assessed. Subsequently, cross-linked copolymers in the powder and film forms with optimal HAS content were synthesized. Their scavenging activities against the three types of radicals were determined, revealing that these hydrogels are potent scavengers of reactive oxygen species.
合成并表征了一系列甲基丙烯酸2-羟乙酯（HEMA）与空间位阻胺衍生物[N-(2,2,6,6-四甲基哌啶-4-基)甲基丙烯酰胺（HAS）]的模型线性共聚物。测定了共聚物对活性氧（过氧自由基和羟基自由基）以及2,2-二苯基-1-苦基肼（DPPH）自由基的清除活性。结果发现，具有中等HAS含量（3.5 - 4.0 mol%）的共聚物比具有较低和较高HAS含量的共聚物以及聚HEMA和聚HAS均聚物和HAS单体是更好的清除剂。重要的是，这些共聚物甚至与既定的低分子量抗氧化剂标准品（丁基羟基茴香醚和泛醇）相比也具有优势。测定了单体反应比，并评估了共聚物的微观结构。随后，合成了具有最佳HAS含量的粉末和薄膜形式的交联共聚物。测定了它们对三种自由基的清除活性，表明这些水凝胶是活性氧的有效清除剂。
