A Comprehensive Review of Niosomes: Composition, Structure, Formation, Characterization, and Applications in Bioactive Molecule Delivery Systems.

Niosomes are nanocarriers with a bilayer structure, consisting of a polar region and a non-polar region. This unique structure allows them to encapsulate compounds with varying polarities, addressing solubility challenges in the transport and delivery of bioactive molecules. The formation of niosomes involves key structural, geometric, and thermodynamic factors influenced by the choice of surfactants and preparation methods. These factors, including the critical packing factor and the hydrophilic-lipophilic balance (HLB), play a crucial role in determining the properties of the final niosomes. Additionally, the use of Tandford's equations allows for the calculation of geometric parameters. These factors determine the structural integrity and functional properties of niosomes, making it possible to design functional niosomes with characteristics tailored for specific applications. This ability to design niosomes with desired properties is especially valuable in biomedical fields, where precise control over drug delivery and targeting is essential. This review highlights the importance of niosome formulation and presents examples of niosomes that have been functionalized for specific applications, including anticancer treatments, immunological treatments, and their action in the central nervous system.