Seite - (000391) - in Biomedical Chemistry: Current Trends and Developments

3.5.5 Cancer Imaging, Diagnostics and Multifuctional Nanosystems The early diagnosis of tumors through screening based on imaging might contribute to the reduction in the mortality for certain types of cancers. Real-time imaging is a most valuable technique that enables visualization of the tissue morphology and cell function, thus allowing the identification of pathological situations that generally cannot be aquired in in vitro analysis (Fass, 2008). Imaging techniques are being combined with nanotechnology, rendering, in many cases, extraordinarily sensitive and powerful diagnostic and imaging tools that, by other means, were not available with small or microscale tools, thus enhancing the tissue contrast or allowing the identification of specific biological changes (Toy, 2014). As it is necessary to specifically target the tumor sites in order to achieve a more successful outcome out of the treatment, it is also of utmost importance that the diagnostic and imaging tools, such as those extensively used in the medical practice: Magnetic Resonance Imaging (MRI), Computed Tomography (CT) and Positron Emission Topography (PET), are reliable enough to facilitate the right medical decisions, which can be improved by alliyng them to nanotechnology (Lee, 2013a; Perez-Medina, 2014). Contrast agents are frequently employed to assist and complement the visualization of abnormalities in a diagnostic image, interacting with the incident radiation to yield noticeable alterations in the final aquired images. They increase the power of the imaging techniques since there is an increased sensitivity, allowing the diagnosis of many diseases that are not possible to detect using conventional methods (Power, 2011). However, nanotechnology is impacting this area of diagnostic imaging by opening new avenues of novel imaging techniques, and by allowing the enhancement of the sensitivity, pharmacokinetics, pharmacodinamics and biocompatibility features of several contrast agents, as well as providing a high signal-to-noise ratio (Rosen JE, 2011). It is becoming inevitable to not associate imaging and therapeutic properties in a single nanoplatform. Multifunctional nanocarriers are becoming more and more fashionable and many studies have been focusing on the production of multistage nanoparticulate systems.