pH-Responsive Catalytic Janus Motors with Autonomous Navigation and Cargo-Release Functions
pH-Responsive Catalytic Janus Motors with Autonomous Navigation and Cargo-Release Functions
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DOI：
10.1002/adfm.202000324
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发表时间：
2020-05-01
影响因子：
19
通讯作者：
Ebbens, Stephen J.
中科院分区：
文献类型：
--
作者：
Archer, Richard A.;Howse, Johnathan R.;Ebbens, Stephen J.
展示了多功能聚合物 Janus 胶体的制造，该胶体表现出催化驱动的推进力，根据局部 pH 值变化而改变其尺寸，并改变货物释放速率。对胶体轨迹的系统研究表明，在酸性环境中，由于胶体膨胀，推进速度急剧降低。这导致低 pH 区域中这些响应颗粒的集合出现类似趋化性的积累。与这种化学定义的积累协同作用，胶体还显示出封装的货物分子的释放速率的增强。总之，这些效应产生了一种策略，利用催化推进来实现由化学刺激引导的联合自主运输和货物释放，显示出超过 30 倍的局部货物积累增强。乳酸可以作为这种行为的刺激物，这是一些肿瘤产生的酸，这表明乳酸可能最终用作药物输送方法。还讨论了微流体传输的应用。
The fabrication of multifunctional polymeric Janus colloids that display catalytically driven propulsion, change their size in response to local variations in pH, and vary cargo release rate is demonstrated. Systematic investigation of the colloidal trajectories reveals that in acidic environments the propulsion velocity reduces dramatically due to colloid swelling. This leads to a chemotaxis-like accumulation for ensembles of these responsive particles in low-pH regions. In synergy with this chemically defined accumulation, the colloids also show an enhancement in the release rate of an encapsulated cargo molecule. Together, these effects result in a strategy to harness catalytic propulsion for combined autonomous transport and cargo release directed by a chemical stimulus, displaying a greater than 30 times local cargo-accumulation enhancement. Lactic acid can be used as the stimulus for this behavior, an acid produced by some tumors, suggesting possible eventual utility as a drug-delivery method. Applications for microfluidic transport are also discussed.