Physical Intelligence Department, Max Planck Institute for Intelligent Systems , 70569 Stuttgart, Germany.
ACS Nano. 2017 Sep 26;11(9):8910-8923. doi: 10.1021/acsnano.7b03207. Epub 2017 Sep 11.
High-performance, multifunctional bacteria-driven microswimmers are introduced using an optimized design and fabrication method for targeted drug delivery applications. These microswimmers are made of mostly single Escherichia coli bacterium attached to the surface of drug-loaded polyelectrolyte multilayer (PEM) microparticles with embedded magnetic nanoparticles. The PEM drug carriers are 1 μm in diameter and are intentionally fabricated with a more viscoelastic material than the particles previously studied in the literature. The resulting stochastic microswimmers are able to swim at mean speeds of up to 22.5 μm/s. They can be guided and targeted to specific cells, because they exhibit biased and directional motion under a chemoattractant gradient and a magnetic field, respectively. Moreover, we demonstrate the microswimmers delivering doxorubicin anticancer drug molecules, encapsulated in the polyelectrolyte multilayers, to 4T1 breast cancer cells under magnetic guidance in vitro. The results reveal the feasibility of using these active multifunctional bacteria-driven microswimmers to perform targeted drug delivery with significantly enhanced drug transfer, when compared with the passive PEM microparticles.
采用优化的设计和制造方法，引入了高性能、多功能的细菌驱动微游泳者，用于靶向药物输送应用。这些微游泳者主要由附着在载药聚电解质多层（PEM）微颗粒表面的单个大肠杆菌细菌组成，微颗粒内部嵌入了磁性纳米颗粒。PEM 药物载体的直径为 1 微米，并且与文献中之前研究的颗粒相比，其材料具有更高的粘弹性。由此产生的随机微游泳者能够以高达 22.5 μm/s 的平均速度游动。它们可以被引导和靶向到特定的细胞，因为它们在化学引诱剂梯度和磁场下分别表现出偏向和定向运动。此外，我们还展示了在体外磁场引导下，这些微游泳者将包裹在聚电解质多层中的阿霉素抗癌药物分子递送到 4T1 乳腺癌细胞。结果表明，与被动 PEM 微颗粒相比，这些主动多功能细菌驱动的微游泳者可用于靶向药物输送，从而显著增强药物传递。
