PDF(Pubmed)
Abstract：
Compared to lipids, block copolymer vesicles are potentially robust nanocontainers for enzymes owing to their enhanced chemical stability, particularly in challenging environments. Herein we report that cis-diol-functional diblock copolymer vesicles can be chemically adsorbed onto a hydrophilic aldehyde-functional polymer brush via acetal bond formation under mild conditions (pH 5.5, 20 °C). Quartz crystal microbalance studies indicated an adsorbed amount, Γ, of 158 mg m-2 for vesicle adsorption onto such brushes, whereas negligible adsorption (Γ = 0.1 mg m-2) was observed for a control experiment conducted using a cis-diol-functionalized brush. Scanning electron microscopy and ellipsometry studies indicated a mean surface coverage of around 30% at the brush surface, which suggests reasonably efficient chemical adsorption. Importantly, such vesicles can be conveniently loaded with a model enzyme (horseradish peroxidase, HRP) using an aqueous polymerization-induced self-assembly formulation. Moreover, the immobilized vesicles remained permeable toward small molecules while retaining their enzyme payload. The enzymatic activity of such HRP-loaded vesicles was demonstrated using a well-established colorimetric assay. In principle, this efficient vesicle-on-brush strategy can be applied to a wide range of enzymes and functional proteins for the design of next-generation immobilized nanoreactors for enzyme-mediated catalysis.
摘要：
与脂质相比，嵌段共聚物囊泡由于其增强的化学稳定性，是酶的潜在强大的纳米容器，特别是在具有挑战性的环境中。在本文中，我们报道了顺式二醇官能二嵌段共聚物囊泡可以在温和条件（pH5.5，20°C）下通过缩醛键形成化学吸附到亲水性醛官能聚合物刷上。石英晶体微天平研究表明吸附量，Γ,Γ158mgm-2用于囊泡吸附到这样的刷子上，而在使用顺式二醇官能化刷进行的对照实验中，观察到可忽略不计的吸附（Γ=0.1mgm-2）。扫描电子显微镜和椭圆光度法研究表明，刷子表面的平均表面覆盖率约为30％，这表明合理有效的化学吸附。重要的是,这样的囊泡可以方便地加载模型酶（辣根过氧化物酶，HRP）使用水性聚合诱导的自组装制剂。此外，固定的囊泡保持对小分子的渗透性，同时保留它们的酶有效载荷。使用建立良好的比色测定法证明了此类HRP负载的囊泡的酶活性。原则上,这种有效的刷上囊泡策略可以应用于广泛的酶和功能蛋白，用于设计用于酶介导催化的下一代固定化纳米反应器。
