Photoinitiated Alkyne-Azide Click and Radical Cross-Linking Reactions for the Patterning of PEG Hydrogels
Photoinitiated Alkyne-Azide Click and Radical Cross-Linking Reactions for the Patterning of PEG Hydrogels
复制标题
DOI：
10.1021/bm201802w
复制
发表时间：
2012-03-01
影响因子：
6.2
通讯作者：
Caruso, Frank
中科院分区：
文献类型：
--
作者：
Chen, Rodney T.;Marchesan, Silvia;Caruso, Frank
描述了仅基于炔官能化的聚（乙二醇）（PEG-四炔）的表面固定和交联的水凝胶的电泳图案化。光生自由基以及通过铜螯合配体的UV吸收导致Cu（II）光化学氧化还原为Cu（I）。这催化炔-叠氮化物点击反应以将水凝胶接枝到叠氮化物官能化的等离子体聚合物（N3 PP）膜上。光生自由基还能够从PEG-四炔中提取氢原子以形成聚（α-烷氧基）自由基。这些自由基可以通过添加到炔和分子间重组来引发交联以形成PEG水凝胶。通过光掩模通过UV曝光在空间上控制这两个光引发的反应导致表面图案化的水凝胶，其厚度可从数十纳米到数百纳米调节。图案化的PEG水凝胶（ca. 60 μ m宽的线）能够抵抗L929小鼠成纤维细胞的附着，导致具有空间受控的细胞附着的表面。图案化的水凝胶表面还表现出空间分辨的化学功能，因为水凝胶的合成后修饰成功地通过随后的炔叠氮化物点击反应用叠氮化物官能化的荧光染料进行。
The photolithographical patterning of hydrogels based solely on the surface immobilization and cross-linking of alkyne-functionalized poly(ethylene glycol) (PEG-tetraalkyne) is described. Photogenerated radicals as well as UV absorption by a copper chelating ligand result in the photochemical redox reduction of Cu(II) to Cu(I). This catalyzes the alkyne-azide click reaction to graft the hydrogels onto an azide-functionalized plasma polymer (N3PP) film. The photogenerated radicals were also able to abstract hydrogen atoms from PEG-tetraalkyne to form poly(alpha-alkoxy) radicals. These radicals can initiate cross-linking by addition to the alkynes and intermolecular recombination to form the PEG hydrogels. Spatially controlling the two photoinitiated reactions by UV exposure through a photomask leads to surface patterned hydrogels, with thicknesses that were tunable from tens to several hundreds of nanometers. The patterned PEG hydrogels (ca. 60 mu m wide lines) were capable of resisting the attachment of L929 mouse fibroblast cells, resulting in surfaces with spatially controlled cell attachment. The patterned hydrogel surface also demonstrated spatially resolved chemical functionality, as postsynthetic modification of the hydrogels was successfully carried out with azide-functionalized fluorescent dyes via subsequent alkyne azide click reactions.