PHYTOSOMES: A NOVEL APPROACH FOR HERBAL DRUG DELIVERY – Review Article

Herbal medicines are rich in diverse bioactive compounds, but the delivery of some phytochemicals is limited by poor aqueous solubility, low membrane permeability, gastrointestinal instability, extensive metabolism, or variable extract composition. Phytosomes are phyto-phospholipid complexes developed to overcome selected delivery barriers, associating plant-derived constituents (flavonoids and other polyphenols) with phospholipids (usually phosphatidylcholine). This association can alter the physicochemical behaviour and enhance compatibility with lipid-rich biological membranes. Herein, the review provides an overview of the structure and composition of phytosomes, proposed mechanisms of formation and delivery, main preparation methods, advantages and limitations, some pharmaceutical applications, evaluation techniques and recent development directions. Commonly used methods such as thin-film hydration, solvent evaporation and anti-solvent precipitation are discussed with the focus on process selection and analytical confirmation. Representative examples are silymarin, curcumin, quercetin and green tea polyphenols. Evidence is graded . Biological plausibility is provided by laboratory and animal findings . Pharmacokinetic studies may show altered exposure . However, these findings alone do not prove clinical efficacy . Characterisation usually includes particle size, polydispersity index, zeta potential, complexation assessment, FTIR, DSC, in vitro release and stability studies. Phytosomes hold promising potential for formulation, but challenges remain, including lipid oxidation, residual solvents, manufacturing costs, variability of the extract, standardisation, and the need for more robust clinical trials. Phytosomes should therefore be considered as a formulation strategy whose merit has to be assessed for each phytoconstituent and product.