Innovative Nano Delivery Systems for Astaxanthin: Enhancing Stability, Bioavailability, and Targeted Therapeutic Applications

Astaxanthin (AST), as a natural antioxidant, has broad application prospects in medicine and health products. However, its highly unsaturated structure and significant lipophilic characteristics limit its dispersibility and bioavailability, thereby restricting its application in food, medicines, and nutraceuticals. To overcome these limitations, researchers have proposed the use of nano delivery systems. This review summarizes various nanocarriers, including liposomes, nanostructured lipid carriers, nanoparticles, and others, and analyzes their advantages in enhancing the solubility, stability, and bioavailability of AST. Furthermore, the study focuses on targeted delivery systems achieved through biomolecular modifications, which enable precise delivery of AST to specific cells or tissues, enhancing therapeutic effects. Additionally, smart-responsive delivery systems, such as pH-responsive and light-sensitive systems, are also discussed, showing their immense potential in precise release and targeted therapy. These findings provide new perspectives for the precise nutrition and clinical applications of AST. Future research should further optimize the design of nanocarriers to enable broader applications.