Theranostic Nanocarriers in Cancer: Dual Capabilities on a Single Platform

The evolution of nanotechnology has ushered in tremendous advances in the field of medicine. Nanocarriers such as liposomes, polymeric and lipidic nanoparticles, micelles, dendrimers, etc., are now used as targeted drug delivery systems that are capable of delivering the therapeutic agent to a specific site in human body. Therapeutic agents such as antimicrobials, anti-HIV, anti-Alzheimer’s, immunosuppressants, peptides, genes, as well as anti-cancer drugs, have been successfully delivered using nanocarriers for the treatment of various diseases. Early diagnosis of the disease is the key for successful management of disease. In the case of cancer, early diagnosis is critical as it can have an impact on the treatment measures and the outcomes of treatment, which affect the quality of life of the patient. The diagnostic tools used nowadays consist of various techniques such as magnetic resonance imaging, optical imaging, computed tomography, etc. These tools require diagnostic agents comprising fluorescent dyes, radioactive elements and contrast agents. These diagnostic agents are frequently administered to the patients along with chemotherapeutic agents for the detection and treatment of cancer or to monitor treatment efficiency, which generally causes toxicity in the patients. This drawback initiated a quest for development of a novel platform that is capable of simultaneous diagnosis and therapy, thereby reducing toxicity in the treatment of cancer. The outcomes of this quest are theranostic nanocarriers, which are the next generation of nanocarriers. They combine the therapeutic moieties as well as the diagnostic agents on a single platform and consist of liposomes, polymeric or metallic nanoparticles, micelles, and dendrimers as carriers. Ideally, theranostic carriers must be capable of incorporating both the diagnostic and therapeutic agents in potent quantities; they must deliver the therapeutic agent to the site of action and should be non-toxic. In this chapter, we discuss the current scenario of theranostic nanocarriers, their methods of synthesis, the diagnostic agents and therapeutic agents used in theranostic nanocarriers and their applications in the management of cancer.