In ligand-based targeting, ligands are conjugated at the periphery of the nanoparticulate system to bind with appropriate receptors at the target tumor site. The targeting ligands can be categorized as proteins (antibody and its fragments), nucleic acids (aptamers), or other ligands (peptides, vitamins, and carbohydrates), which generally bind to the receptor uniquely overexpressed by tumor cells or vasculature.21–23 The targeting ligands play a vital role in enhancing cellular uptake of NPs through the process of endocytosis. Long-circulating NPs enable their efficient delivery to the tumor site by the EPR phenomena, and internalization of the nanosystem results in improved therapeutic effect.24–27 The cellular targets for this strategy have been identified on the tumor cell and endothelium.