Fig. 1. Structural design, function and application of MagCaps.

a Structure of the MagCaps and drug injection process. b Schematic diagram showing the opening and closing process of the soft valve under an external magnetic field. c Schematic diagram of the human GI tract and the ingestible capsule, the figure was partly generated using Servier Medical Art, provided by Servier, licensed under a Creative Commons Attribution 3.0 unported license⁷¹. d Schematic diagram showing the multi-target drug release process in the stomach. e Schematic diagram of the sampling process in the small intestine. f Photographs of the developed 6 MagCaps (Miniature Cap1, Visualization Cap2, Dual-module Cap3, Threaded Cap4, Light-assisted Cap5, Thermal-assisted Cap6). Scale bar: 10 mm.