Biotechnological approaches toward nanoparticle biofunctionalization.

Nanomedicine has emerged in the past decade as a promising tool for several therapeutic and diagnostic applications. The development of nanoconjugates containing bioactive ligands specific for targeting cancer cell receptors has become a primary objective of modern nanotechnology. The design of ideal nanoconjugates requires optimization of fundamental parameters including size, shape, ligand shell composition, and reduction in nonspecific protein adsorption. Of great importance is the choice of bioconjugation approach, given that it affects the orientation, accessibility, and bioactivity of the targeting molecule. We provide an overview of recent advances in the immobilization of targeting proteins, focusing on methods to control ligand orientation and density, and highlight criteria for nanoparticle design and development required to achieve enhanced receptor-targeting efficiency.