Electrosprayed PLA/Spirulina Hybrid Microparticles for Enhanced Dermal Delivery on HUVEC and HaCaT Cell Lines of Niacinamide and Palmitoyl-Tripeptide-1

Developing advanced delivery systems for dermal applications requires innovative approaches to overcome compound solubility, stability, and cellular uptake limitations. This study develops electrosprayed poly(lactic acid)/Spirulina (PLA/Spi) hybrid microparticles for efficient dermal delivery of hydrophilic (niacinamide) and lipophilic (palmitoyl-tripeptide-1) compounds. The optimized microparticles demonstrated remarkable dose-sparing effects, achieving comparable bioactivity at reduced concentrations versus free compounds. Cellular uptake peaked at 5 mu g/mL in endothelial cells (HUVEC, 44.5%) and keratinocytes (35.6%), showing an inverse concentration-uptake relationship linked to improved particle dispersion. The system maintained excellent biocompatibility while exhibiting cell-specific responses: enhanced endothelial proliferation with encapsulated palmitoyl-tripeptide-1 and improved keratinocyte migration with niacinamide. Notably, the Spirulina carrier displayed intrinsic wound-healing activity. These findings highlight the platform's potential for dermatological applications, offering simultaneous delivery of diverse bioactives with dramatically reduced dosage requirements. The observed particle-cell interactions suggest novel mechanisms for optimizing delivery efficiency, warranting further investigation of underlying cellular processing pathways. This technology shows promise for wound healing, photoprotection, and targeted dermal therapies.