Applications for site-directed molecular imaging agents coupled with drug delivery potential

Molecular imaging allows non-invasive characterization and quantification of biological processes at cellular and molecular level. Such technologies make it possible to enhance our understanding of drug activity and pharmokinetic properties, and therefore aid decisions to select candidates that are most likely to benefit from targeted drug therapy. Targeted DDSs are nanometer-sized carrier materials designed for improving the biodistribution of systemically applied (chemo-)therapeutics by strictly localizing its pharmacological activity to the site or organ of action. The parallel development of molecular imaging and targeted drug delivery offers great challenges and opportunities for a single multifunctional platform technology, combining targeted motif, therapeutic agents and imaging agents for imaging guided drug delivery. This review article summarizes the synthesis and characterization of various biomaterials that carry targeting motifs, imaging tags and therapeutic agents as theragnostics.