ABSTRACT
In vivo imaging is continuously gaining interest as an efficient noninvasive technique of testing new biomolecules, drugs, and nanoparticles (NPs) in vivo. Over the past 30 years, various physical principles describing interaction between radiation and matter have been explored, leading to a number of exciting methodologies that provide anatomic, functional, metabolic, and molecular information. Nanotechnology is obviously a field that has benefitted a lot from in vivo imaging, although its use as a standard part of nanosystems evaluation is not established. X-rays have been used in medicine as the basis of the first anatomical imaging technique, which continues to evolve up to now. It is based on the simple transmission of X-rays, which are emitted from a source (usually an X-ray tube) and are recorded from an analog or digital detector. Today CT imaging is usually a stand-alone anatomical technique or is combined with other molecular imaging techniques to provide the anatomical map of an animal or a human.
