Silk fibroin nanoparticles coated with secretome-derived extracellular vesicles via GMP-ready microfluidics: a biomimetic carrier-in-carrier platform with preferential tumor cell internalization.

The integration of synthetic nanocarriers with biologically derived membranes represents a promising strategy to engineer biomimetic systems for precision medicine. Here, we report a hybrid nanoplatform in which silk fibroin nanoparticles (SFNs) are coated with the vesicular fraction of a GMP-compliant lyosecretome (herein referred to as secretome-derived EVs), in a hierarchical carrier-in-carrier architecture, enabling the combination of tunable material properties with intrinsic biological functionality. A key advancement of this work is the development of a microfluidic, GMP-compatible assembly process that allows controlled and scalable production of secretome-derived EV-coated nanoparticles, addressing a major translational bottleneck in the field. The resulting hybrid nanostructures were characterized by nanoparticle tracking analysis and Förster resonance energy transfer, confirming nanoscale proximity between SFN surfaces and EV membranes consistent with EV membrane association. Using a model lipophilic compound, we demonstrate that EV-membrane association enhances colloidal stability, protects the payload from degradation, and enables sustained release profiles. Importantly, the biological identity of the secretome-derived EV membrane was found to modulate cellular interactions: EVs derived from mesenchymal stromal cells promoted preferential uptake in healthy cells, whereas tumor-derived EVs drove selective internalization in homologous cancer cells in vitro. These findings establish EV-coated SFNs as a versatile biomimetic platform with programmable cell-type-specific uptake properties and scalable manufacturability, providing a foundation for the development of next-generation nanotherapeutics that integrate material design with biological specificity for precision oncology.