Polysaccharides as nanocarriers for therapeutic applications.

Nanocarriers have shown tremendous potential for the target-specific delivery of proteins, genes and drugs. Nanoparticles are fabricated using different natural and synthetic polymers. Natural polysaccharides are often used as building block for developing nano-sized drug delivery vehicles. The physicochemical properties of these materials, such as excellent biocompatibility, low cytotoxicity, surface charges that interact with DNA, protein and RNA, and cost effectiveness, make them exceptional base materials for nanocarrier fabrication. The mechanism for the complex formation of polysaccharides-DNA includes the electrostatic interactions between cationic polymers and anionic DNA to form polyplexes that offer unique possibilities for overcoming cellular barriers by escaping endosomal trafficking followed by cellular internalization and, consequently, enhancing the efficacy of drug and macromolecule delivery to targeted cells and tissue. Depending upon the cellular uptake and trafficking, nanocarriers are designed for different pharmacological and therapeutic applications. However, specific targeting that improves delivery remains an unsolved challenged. The process by which nanocarriers enter cells has important consequences not only for fate of these particles but also for biological systems and therapeutic applications.