The use of micromotors for active drug delivery via oral administration has recently gained considerable interest. However, efficient motor-assisted delivery into the gastrointestinal (GI) tract remains challenging, owing to the short propulsion lifetime of currently used micromotor platforms. Here, we report on an efficient algae-based motor platform, which takes advantage of the fast and long-lasting swimming behavior of natural microalgae in intestinal fluid to prolong local retention within the GI tract. Fluorescent dye or cell membrane–coated nanoparticle functionalized algae motors were further embedded inside a pH-sensitive capsule to enhance delivery to the small intestines. In vitro, the algae motors displayed a constant motion behavior in simulated intestinal fluid after 12 hours of continuous operation. When orally administered in vivo into mice, the algae motors substantially improved GI distribution of the dye payload compared with traditional magnesium-based micromotors, which are limited by short propulsion lifetimes, and they also enhanced retention of a model chemotherapeutic payload in the GI tract compared with a passive nanoparticle formulation. Overall, combining the efficient motion and extended lifetime of natural algae–based motors with the protective capabilities of oral capsules results in a promising micromotor platform capable of achieving greatly improved cargo delivery in GI tissue for practical biomedical applications.

中文翻译：

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使用嵌入可降解胶囊中的藻类马达进行胃肠道药物输送

使用微电机通过口服进行主动药物输送最近引起了相当大的兴趣。然而，由于目前使用的微电机平台的推进寿命较短，有效的电机辅助输送到胃肠道（GI）仍然具有挑战性。在这里，我们报告了一种基于藻类的高效运动平台，该平台利用肠液中天然微藻的快速且持久的游泳行为来延长胃肠道内的局部保留。荧光染料或细胞膜涂覆的纳米颗粒功能化藻类马达进一步嵌入 pH 敏感胶囊内，以增强向小肠的输送。在体外，藻类电机在模拟肠液中连续运行 12 小时后表现出恒定的运动行为。当小鼠体内口服给药时，与传统的镁基微电机相比，藻类电机大大改善了染料有效负载的胃肠道分布，而传统的镁基微电机受到推进寿命短的限制，并且与传统的镁基微电机相比，它们还增强了模型化疗有效负载在胃肠道中的保留。采用被动纳米颗粒配方。总的来说，将天然藻类电机的高效运动和延长的使用寿命与口服胶囊的保护能力相结合，形成了一个有前途的微电机平台，能够大大改善胃肠道组织中的货物输送，用于实际的生物医学应用。