Processing\nSolid Hydrogels into Hollow Structures\nby Infrared Laser Light for Highly-Efficient Drug Loading and Controlled\nRelease

Hollow\nhydrogels, characterized by their three-dimensional networks\nakin to biological tissues, are extensively utilized in artificial\nblood vessels, drug delivery, and nerve conduits due to their superior\nbiocompatibility and fluid-transportation capacity. Nonetheless, the\nfabrication of hollow hydrogels presents significant challenges, including\nintricate steps, costly equipment, and structural instability. Consequently,\nrefining the preparation techniques for hollow hydrogels remains paramount\nto surmounting the limitations of conventional methods. This research\nintroduces an innovative approach that markedly diverges from traditional\ntechniques, offering notable convenience and efficiency in the creation\nof hollow hydrogel structures. The central novelty of this method\nlies in employing laser light to induce an in situ photothermal effect,\nleading to the formation of hollow configurations. This laser-driven\ntransformation of solid hydrogels into hollow structures addresses\nnumerous shortcomings associated with traditional methods. For instance,\nconventional chemical approaches often necessitate several days to\nyield hollow hydrogels, and the resultant structures tend to be fragile\nand susceptible to damage under external pressure. In contrast, the\nlaser-assisted technique facilitates the formation of hollow structures\nwithin 240 s, significantly outpacing traditional methods. To achieve\ncontrolled drug release, silk fibroin was integrated into the wall\nof the hollow hydrogels, enabling modulation of wall permeability\nand directing the drug release process.