A Magnetic Bio‐Inspired Soft Carrier as a Temperature‐Controlled Gastrointestinal Drug Delivery System

• Published in: Macromolecular bioscience 2023-07, Vol.23 (7), p.e2200559-n/a
• Main Authors: Heunis, Christoff M., Wang, Zhuoyue, de Vente, Gerko, Misra, Sarthak, Venkiteswaran, Venkatasubramanian Kalpathy
• Format: Article
• Language: English
• Subjects: Actuation; biomedical soft robots; Controlled release; Drug delivery; Drug delivery systems; Drug Delivery Systems - methods; Drug development; Endoscopes; Ethylene glycol; Excipients; Fabrication; Gastrointestinal Agents; Gastrointestinal system; Gastrointestinal tract; Glycol dimethacrylates; Intestine; Large intestine; magnetic actuation; Magnetic Phenomena; Molding (process); Polymers; Prototypes; Shape memory; shape memory polymers; Small intestine; Temperature; Transition temperature; Transition temperatures
• ISSN: 1616-5187; 1616-5195
• DOI: 10.1002/mabi.202200559

Currently, gastrointestinal bleeding in the colon wall and the small bowel is diagnosed and treated with endoscopes. However, the locations of this condition are often problematic to treat using traditional flexible and tethered tools. New studies commonly consider untethered devices for solving this problem. However, there still exists a gap in the extant literature, and more research is needed to diagnose and deliver drugs in the lower gastrointestinal tract using soft robotic carriers. This paper discusses the development of an untethered, magnetically‐responsive bio‐inspired soft carrier. A molding process is utilized to produce prototypes from Diisopropylidene‐1,6‐diphenyl‐1,6‐hexanediol‐based Polymer with Ethylene Glycol Dimethacrylate (DiAPLEX) MP‐3510 ‐ a shape memory polymer with a low transition temperature to enable the fabrication of these carriers. The soft carrier design is validated through simulation results of deformation caused by magnetic elements embedded in the carrier in response to an external field. The thermal responsiveness of the fabricated prototype carriers is assessed ex vivo and in a phantom. The results indicate a feasible design capable of administering drugs to a target inside a phantom of a large intestine. The soft carrier introduces a method for the controlled release of drugs by utilizing the rubbery modulus of the polymer and increasing the recovery force through magnetic actuation. An untethered, magnetically‐responsive soft carrier can be used to deliver drugs in the lower gastrointestinal tract. This design utilizes a shape memory polymer, DiAPLEX MP‐3510, to enable the carrier to be molded and activated by magnetic elements. The thermal responsiveness of the carrier is tested in a phantom of a large intestine, and simulation results show successful deformation in response to an external magnetic field. This design offers a controlled release of drugs and a new way to treat gastrointestinal bleeding with traditionally difficult‐to‐reach areas.