Liu Xinyue, Yang Yueying, Inda Maria Eugenia, Lin Shaoting, Wu Jingjing, Kim Yoonho, Chen Xiaoyu, Ma Dacheng, Lu Timothy K, Zhao Xuanhe
Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Synthetic Biology Group, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Adv Funct Mater. 2021 Jul 2;31(27). doi: 10.1002/adfm.202010918. Epub 2021 Apr 23.
Natural microbial sensing circuits can be rewired into new gene networks to build living sensors that detect and respond to disease-associated biomolecules. However, synthetic living sensors, once ingested, are cleared from the gastrointestinal (GI) tract within 48 hours; retaining devices in the intestinal lumen is prone to intestinal blockage or device migration. To localize synthetic microbes and safely extend their residence in the GI tract for health monitoring and sustained drug release, an ingestible magnetic hydrogel carrier is developed to transport diagnostic microbes to specific intestinal sites. The magnetic living hydrogel is localized and retained by attaching a magnet to the abdominal skin, resisting the peristaltic waves in the intestine. The device retention is validated in a human intestinal phantom and an rodent model, showing that the ingestible hydrogel maintains the integrated living bacteria for up to seven days, which allows the detection of heme for GI bleeding in the harsh environment of the gut. The retention of microelectronics is also demonstrated by incorporating a temperature sensor into the magnetic hydrogel carrier.
天然微生物传感电路可以重新布线到新的基因网络中，以构建能够检测并响应疾病相关生物分子的活体传感器。然而，合成活体传感器一旦被摄入，会在48小时内从胃肠道清除；将装置保留在肠腔内容易导致肠道堵塞或装置迁移。为了定位合成微生物并安全地延长它们在胃肠道中的停留时间以进行健康监测和持续药物释放，开发了一种可摄入的磁性水凝胶载体，用于将诊断微生物运输到特定的肠道部位。通过将磁铁附着在腹部皮肤上来定位并保留磁性活体水凝胶，以抵抗肠道中的蠕动波。该装置的保留在人体肠道模型和啮齿动物模型中得到验证，表明可摄入水凝胶可使完整的活菌维持长达七天，这使得在肠道的恶劣环境中能够检测到用于胃肠道出血的血红素。通过将温度传感器集成到磁性水凝胶载体中，还证明了微电子设备的保留。
