Preparation of a new liquid dosage from Vitamin D<sub>3</sub> by using pospholipid conjugate

Vitamin D3 has poor solubility in water, leading to a low dissolution profile, which presents significant biopharmaceutical challenges. To overcome these issues, liposome-conjugation techniques have been researched in recent years. Liposomes can enhance the solubility, stability, and bioavailability of vitamin D3, improving its therapeutic effectiveness. The study aimed to prepare and evaluate the particles for vitamin D3 conjugated with phospholipids, focusing on optimizing their formulation, assessing stability, and enhancing bioavailability. Vitamin D3 conjugated with phospholipids was prepared using the solvent evaporation method in a 1:1 ratio. The conjugation greatly improved the physical properties of the vitamin D3 in its conjugation and dispersion in a significant way; then the conjugate was characterized by using x-ray diffraction (XRD), fourier transforms infrared spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), optical microscope (Op.M)toconfirm the formation of a complex between vitamin D3 and phospholipids. The polydispersity index and zeta potential of the prepared vitamin D3-phosphatidylcholine conjugate were measured as 74.96 and −56.93 mV, respectively, confirming its colloidal stability. These values indicated uniform particle size distribution and strong electrostatic repulsion, preventing aggregation. Additionally, the solubility in water was studied and compared with pure vitamin D3, demonstrating improved solubility characteristics of the conjugate. This work suggests using liposomal formulations of vitamin D3-phosphatidylcholine conjugates as an alternative to conventional vitamin D3 tablets. These formulations can potentially enhance drug absorption and bioavailability, allowing for dose reduction and minimizing side effects. Additionally, improved bioavailability may lead to better patient compliance and therapeutic outcomes, offering a more efficient approach to vitamin D3 supplementation.