Piras Carmen C, Smith David K
Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK.
Chemistry. 2019 Aug 27;25(48):11318-11326. doi: 10.1002/chem.201902158. Epub 2019 Aug 1.
A two-component self-sorting hydrogel based on acylhydrazide and carboxylic acid derivatives of 1,3:2,4-dibenzylidene-d-sorbitol (DBS-CONHNH and DBS-COOH) is reported. A heating-cooling cycle induces the self-assembly of DBS-CONHNH , followed by the self-assembly of DBS-COOH induced by decreasing pH. Although the networks are formed sequentially, there is spectroscopic evidence of interactions between them, which impact on the mechanical properties and significantly enhance the ability of these low-molecular-weight gelators (LMWGs) to form gels when mixed. The DBS-COOH network can be switched "off" and "on" within the two-component gel through a pH change. By using a photo-acid generator, the two-component gel can be prepared combining the thermal trigger with photo-irradiation. Photo-patterned self-assembly of DBS-COOH within a pre-formed DBS-CONHNH gel under a mask yields spatially controlled multi-domain gels. Different gel domains can have different functions, for example, controlling the rate of release of heparin incorporated into the gel, or directing gold nanoparticle assembly. Such photo-patterned multi-component hydrogels have potential applications in regenerative medicine or bio-nano-electronics.
报道了一种基于1,3:2,4-二亚苄基-d-山梨醇的酰肼和羧酸衍生物（DBS-CONHNH和DBS-COOH）的双组分自分类水凝胶。加热-冷却循环诱导DBS-CONHNH的自组装，随后通过降低pH值诱导DBS-COOH的自组装。尽管网络是依次形成的，但有光谱证据表明它们之间存在相互作用，这会影响机械性能，并显著增强这些低分子量凝胶剂（LMWGs）混合时形成凝胶的能力。通过改变pH值，DBS-COOH网络可以在双组分凝胶中“关闭”和“打开”。通过使用光酸发生器，可以将热触发与光照射相结合来制备双组分凝胶。在掩膜下，DBS-COOH在预先形成的DBS-CONHNH凝胶内进行光图案化自组装，产生空间可控的多域凝胶。不同的凝胶域可以具有不同的功能，例如，控制掺入凝胶中的肝素的释放速率，或引导金纳米颗粒组装。这种光图案化的多组分水凝胶在再生医学或生物纳米电子学中具有潜在应用。
