A Transformable Mucoadhesive Microgel Network for Noninvasive Multimodal Imaging And Radioprotection of A Large Area of The Gastrointestinal Tract.

The lack of noninvasive imaging and modulation of a large area of the gastrointestinal (GI) tract constrains the diagnosis and treatment of many GI-related diseases. Recent advances use novel mucoadhesive materials to coat a part of the GI tract and then modulate its functions. The high mucoadhesion is the key factor of the partial coating, but also the limitation for not spreading and covering the lower GI tract. Here, we screened and engineered a bismuth-pectin organic-inorganic hybrid complex into a transformable microgel network (Bi-GLUE) with high flowability and mucoadhesion that can quickly transit through and coat a large area of the GI tract. In murine and porcine models, Bi-GLUE delivered contrast agents to achieve real-time, large-area GI tract imaging under X-ray or MR modalities and facilitated the non-invasive diagnosis of familial adenomatous polyposis. Moreover, Bi-GLUE, like an intracorporal radiation shield, decreases the radiotoxicity in a whole-abdomen irradiation rat model. This transformable microgel network offers a new direction that can modulate a large area of the GI tract and may have broad applications for GI-related conditions. This article is protected by copyright. All rights reserved.