A Twin-Fluid Atomization Method for Fabricating Ovalbumin-Loaded Gelatin Microcapsules

Gelatin is an attractive wall material for microcapsule fabrication because it enables solvent-free processing. However, conventional gelatin microcapsules typically require chemical crosslinkers for structural stabilization, which may raise safety concerns and compromise the bioactivity of encapsulated protein therapeutics or antigens. Herein, we report a crosslinker-free method for fabricating gelatin microcapsules via twin-fluid spray-droplet atomization using a full-cone nozzle. Gelatin microcapsules loaded with ovalbumin (OVA), a model protein (antigen), were successfully prepared without chemical crosslinking, and the encapsulated antigen retained its in vivo antigenicity, indicating that its biological function was preserved.