Amphiphilic Gelator-Based Shear-Thinning Hydrogel for Minimally Invasive Delivery Via Endoscopy Catheter to Remove Gastrointestinal Polyps

Easily injectable polymeric hydrogels via an endoscopic catheter have attracted significant attention for their employment as submucosal materials to develop long-lasting cushions and subsequently facilitate the removal of small, flat polyps from the gastrointestinal tract during endoscopic submucosal dissection (ESD). However, several polymer-based submucosal injections tested in large animal models do not meet the easy-injectability criteria via catheter because of their high inherent viscosity, quick gelation, and catheter needle clogging. Here, we engineered a novel amphiphile diglycerol monostearate (DGMS) based self-assembled hydrogel for minimal delivery via endoscopy catheter. The detailed physiochemical characterization studies for hydrogel support fibrous morphology, shear-thinning property, gelation, easy injectability via needles of various gauge sizes (18 G, 21 G, 24 G, 26 G), reproducibility, and stability. This self-assembled hydrogel can encapsulate hydrophobic and hydrophilic therapeutics, such as blood clotting molecules and anticancer drugs. Ex vivo studies conducted on goat stomachs and intestines demonstrate the feasibility of injectability through a standard endoscopy catheter and the development of visible and long-lasting cushions. In vivo studies in small animals extensively support desirable features of the hydrogel platform, including stability, biocompatibility, non-immunogenic, and blood clotting ability. Endoscopic studies in the porcine model show that the hydrogel platform is a safe submucosal injection that can potentially improve the treatment outcomes in early endoscopic excision of gastrointestinal polyps. This study sets an example for engineering novel small molecules-based shear-thinning hydrogel for biomedical applications.