Institute of Organic and Macromolecular Chemistry , Heinrich-Heine-University Düsseldorf , Universitätsstraße 1 , 40225 Düsseldorf , Germany.
Otto Diels Institute of Organic Chemistry , Christiana Albertina University of Kiel , Otto-Hahn-Platz 3/4 , 24098 Kiel , Germany.
ACS Appl Mater Interfaces. 2019 Jul 31;11(30):26674-26683. doi: 10.1021/acsami.9b08537. Epub 2019 Jul 19.
The synthesis of carbohydrate-functionalized thermosensitive poly(-isopropylacrylamide) microgels and their ability to bind carbohydrate-binding pathogens upon temperature switch are reported. It is found that the microgels' binding affinity is increased above their lower critical solution temperature (LCST), enabling thermo-triggerable capture of pathogens. Here, a series of microgels with comparatively low mannose functionalization degrees below 1 mol % is achieved by a single polymerization step. Upon increase in mannose density, the microgel size increases, and the LCST decreases to 26 °C. Clustering with concanavalin A indicated that binding affinity is enhanced by a higher mannose content and by raising the temperature above the LCST. Binding studies with confirm stronger specific interactions above the LCST and formation of mechanically stable aggregates enabling efficient separation of by filtration. For small incubation times above the LCST, the microgels' potential to release pathogens again below the LCST is confirmed also. Compared to existing switchable scaffolds, microgels nearly entirely composed of a thermosensitive material undergo a large change in volume, which allows them to drastically vary the density of ligands to switch between capture and release. This straightforward yet novel approach is likely compatible with a broad range of bioactive ligands. Therefore, thermosensitive microgels represent a promising platform for the specific capture or release of cells or pathogens.
报道了糖基化温敏聚（异丙基丙烯酰胺）微凝胶的合成及其在温度切换时与糖结合病原体结合的能力。研究发现，微凝胶的结合亲和力在其低临界溶液温度（LCST）以上增加，从而能够实现对病原体的热触发捕获。在此，通过单一聚合步骤实现了一系列比较低的甘露糖官能化度（低于 1 摩尔%）的微凝胶。随着甘露糖密度的增加，微凝胶的尺寸增大，LCST 降低至 26°C。与伴刀豆球蛋白 A 的聚集表明，结合亲和力通过更高的甘露糖含量和将温度升高到 LCST 以上来增强。与 的结合研究表明，在 LCST 以上具有更强的特异性相互作用，并形成机械稳定的聚集体，从而能够通过过滤有效地分离 。对于 LCST 以上的小孵育时间，微凝胶再次在 LCST 以下释放病原体的潜力也得到了证实。与现有的可切换支架相比，几乎完全由热敏材料组成的微凝胶体积发生了很大变化，这使它们能够在捕获和释放之间剧烈改变配体的密度。这种简单而新颖的方法可能与广泛的生物活性配体兼容。因此，温敏微凝胶是一种有前途的特定捕获或释放细胞或病原体的平台。
