Process-guided design of nanoliposomal vitamin D3: formulation, stability and quality by design mapping

The development of aqueous vitamin D3 supplements remains challenging because the molecule is poorly soluble, chemically fragile, and prone to loss of potency during storage. In this work, we adopted a Quality-by-Design (QbD) strategy to construct a nanoliposomal structure able to protect and deliver vitamin D3 while maintaining technological simplicity and high tolerability. As a first step, drug-free nanoliposomes were produced using a coaxial-jet mixer and systematically investigated through a Box–Behnken Design. This approach allowed us to identify the critical relationships between phosphatidylcholine concentration, solvent/antisolvent flow rates, and the resulting nanoliposomal architecture, thereby defining a robust design space for nano-vesicle formation. Vitamin D3 was then introduced into the optimized system to verify process transferability. Encapsulation proved efficient and compatible with the micromixing-driven assembly of nanoliposomes, and the formulation was subsequently subjected to accelerated and real-time stability studies. These experiments revealed a clear hierarchy of stabilizing effects, highlighting the combined protective role of the liposomal bilayer and a carefully balanced antioxidant environment. Building on these findings, the research formulation was further refined into a commercially viable product, described in a dedicated patent, and benchmarked against leading marketed references. The final dispersion exhibited high structural uniformity, stable vitamin retention and manufacturing features consistent with large-scale implementation. Overall, this work demonstrates how a QbD-guided pathway — from mechanistic process mapping to stability-driven optimization and product translation — can yield a high-quality nanoliposomal vitamin D3 with clear technological and practical advantages.