Bioinspired Liquid Pockets with Externally Induced Internal Microscale Flow.

The gastric mucosal barrier, through its gastric pits, serves as a pathway for secretions, ensuring that mucus produced by the gastric glands is transferred to the gastric lumen, providing stable protection. Here a bioinspired liquid pockets material is shown, composed of a thermo-driven hydrogel that acts as an external activation unit to release interflowing liquid responsively, and porous matrices that serve as interconnected pockets to transfer it, enabling controlled internal flow and adaptive barrier functionality. Experiments and theoretical analysis demonstrate the stability and regulatory mechanisms of these liquid pockets, based on the interconnected pockets between the external activation unit and internal fluid flow. It exhibits a new pathway for regulating microscale flow at responsive material interfaces, enabling applications from sequential drug release, self-cleaning, and antifouling to anti-swelling. These unique capabilities address long-standing challenges in microscale flow control, with potential impacts in diverse fields including microfluidics, drug delivery, medical devices, 3D printing, and beyond.