Saha Sampa, Bruening Merlin L, Baker Gregory L
Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA.
Macromolecules. 2012 Nov 27;45(22). doi: 10.1021/ma301556v.
Azidopropyl methacrylate (AzPMA), a functional monomer with a pendent azido group, polymerizes from surfaces and provides polymer brushes amenable to subsequent elaboration via click chemistry. In DMF at 50 °C, click reactions between poly(AzPMA) brushes and an alkynylated dye proceed with >90% conversion in a few minutes. However, in aqueous solutions, reaction with an alkyne-containing poly(ethylene glycol) methyl ether (mPEG, =5000) gives <10% conversion after a 12-h reaction at room temperature. Formation of copolymers with AzPMA and polyethylene glycol methyl ether methacrylate (mPEGMA) enables control over the hydrophilicity and functional group density in the copolymer to increase the yield of aqueous click reactions. The copolymers show reaction efficiencies as high as 60%. These studies suggest that for aqueous applications such as bioconjugation via click chemistry, control over brush hydrophilicity is vital.
甲基丙烯酸叠氮丙酯（AzPMA）是一种带有侧叠氮基的功能单体，可从表面聚合，并提供适合通过点击化学进行后续加工的聚合物刷。在50℃的N，N - 二甲基甲酰胺（DMF）中，聚（AzPMA）刷与炔基化染料之间的点击反应在几分钟内转化率> 90％。然而，在水溶液中，与含炔基的聚（乙二醇）甲醚（mPEG，= 5000）反应在室温下反应12小时后转化率<10％。与AzPMA和聚乙二醇甲基醚甲基丙烯酸酯（mPEGMA）形成共聚物能够控制共聚物中的亲水性和官能团密度，以提高水性点击反应的产率。共聚物显示出高达60％的反应效率。这些研究表明，对于诸如通过点击化学进行生物共轭的水性应用，控制刷的亲水性至关重要。
