Bioinspired Synthesis of Zeolitic Imidazolate Framework-8 in Giant Unilamellar Vesicles

The confined synthesis of functional nanomaterials within biomimetic compartments offers a strategy to address key limitations in biomedical applications, including stability, biocompatibility, and controlled encapsulation. Here, we report the in situ precipitation of zeolitic imidazolate framework-8 (ZIF-8) within phospholipid giant unilamellar vesicles (GUVs). By encapsulating Zn 2+ in the vesicle lumen and triggering crystallization through external addition of membrane-permeable 2-methylimidazole, we establish a bioinspired compartmentalized synthesis approach. Confocal and electron microscopy confirm nanoparticle formation and reveal strong interactions between the precipitated phase and the membrane, leading to poration and selective content release. Crystal-size analysis and comparison with bulk systems show that confinement and the lipid interface modulate nucleation and growth. These results identify GUVs as soft templates for localized nanomaterial synthesis and as modular platforms for drug delivery, bioresponsive systems, and synthetic cell design.