Electrostatic Patterning of Nanofibrous Microcapsules for Three-Dimensional Cell Culture.

Three-dimensional biomaterial scaffolds with controlled geometry and surface nanoarchitecture are essential for advancing polymer processing strategies in tissue engineering. Conventional electrospinning generates nanofibrous structures but has limited ability to reproduce defined three-dimensional shapes or achieve high pattern fidelity. This study aimed to develop a scalable processing method for producing biodegradable scaffolds with precisely controlled microstructure and geometry using phase separation-assisted electrospray. Poly (lactic acid) microcapsules with tunable diameters and porous nanofibrous surfaces were fabricated under controlled humidity and deposited onto conductive molds to obtain two- and three-dimensional scaffold shapes. The manufacturing process required only simple electrospray equipment and static molds, without mechanically complex collectors or moving stages. The resulting scaffolds replicated mold features with resolutions down to 200 μm and achieved thickness up to 600 μm. The nanofibrous microcapsule surfaces supported strong adhesion and metabolic activity of HepG2 cells, while cellular penetration into deeper scaffold regions remained limited to approximately 80 μm. These findings indicate that electrospray-mediated microcapsule deposition is a practical polymer-processing approach that integrates nanofibrous surface formation with mold-defined shaping, offering a reproducible and scalable method for fabricating structurally precise and biologically compatible three-dimensional scaffolds.