8 - Synthesis and applications of functionalized nanoparticles in biomedicine and radiotherapy

Abstract

Functionalized nanomaterials such as metal and magnetic nanoparticles are effective radiosensitizers in medical imaging and cancer therapy. In biomedical and cancer therapeutic applications, functionalized nanomaterials such as gold nanoparticles can act as a contrast agent and dose enhancer in image-guided nanoparticle-enhanced radiotherapy using kilovoltage cone-beam computed tomography. Similarly, magnetic nanoparticles made of iron or iron oxide can act as a contrast agent in magnetic resonance imaging and an enhancer in thermotherapy such as hyperthermia. With recent advances of synthesis and fabrication methods in nanomaterials, particle variables such as size, composition, morphology, and surface chemistry can easily be controlled by precise technology. Moreover, biocompatible surface coating can be added on the nanoparticle surface to provide stabilization under physiological condition. The integration of functional ligands as coating through surface chemistry on the nanoparticles enables them to perform multiple biomedical functions at the molecular or cellular level simultaneously. Applications of these nanomaterials include contrast agents in multimodal imaging, carriers in drug delivery, and enhancers in cancer therapy. In this chapter, we will review different synthesis methods to fabricate functionalized nanomaterials such as chemical coprecipitation, high-temperature decomposition of organic surfactants, microemulsions, and laser pyrolysis. We will also explore different applications of nanomaterials in biomedicine and radiotherapy such as using magnetic nanoparticles as an enhancer in magnetic resonance imaging and hyperthermia, and heavy-atom nanoparticles in kilovoltage computed tomography and cancer therapy.