Pharmaceutical and biomedical potential of PEGylated dendrimers

The development of dendritic architecture with well-defined size, shape and controlled exterior functionality holds promise in pharmaceutical applications such as drug delivery, solubilization, DNA transfection and diagnosis. Highly branched, monodisperse, stable molecular level and low polydispersity with micelle-like behavior possessing nano-scale container property distinguish these structures as inimitable and optimum carrier for those applications. However reticuloendothelial system (RES) uptake, drug leakage, immunogenicity, hemolytic toxicity, cytotoxicity, hydrophobicity restrict the use of these nanostructures. PEGylation of dendrimers can generally overcome these shortcomings. Hemolytic and different cell line studies have shown reduced toxicity of PEGylated dendrimers than cationic dendrimers. PEGylation causes increased solubilization of hydrophobic drugs in dendritic framework as well as in PEG layers. PEGylated dendrimers have proved capable or forming stable complex with plasmid DNA and achieved improved gene transfection as compared to non-PEGylated dendrimers. Attachments of targeting moiety on the surface of partially PEGylated dendrimer created much interest as a delivery system for crossing of biological barriers and deliver the bioactive agent near the vicinity of target site. Recent successes also demonstrate potential of PEGylated dendrimers as magnetic resonance imaging contrast agent and in carbonyl metallo immunoassay. This review focuses on the current state of the art in the field and focuses on the potential of PEGylated dendrimers in pharmaceutical and biomedical area.