# Gold Nanoparticles and Nanorods in Nuclear Medicine: A Mini Review
###### Abstract  
In the last decade, many innovative nanodrugs have been developed, as well as many nanoradicompounds that show amazing features in nuclear imaging and/or radiometabolic therapy. Their potential uses offer a wide range of possibilities. It can be possible to develop nondimensional systems of existing radiopharmaceuticals or build engineered systems that combine a nanoparticle with the radiopharmaceutical, a tracer, and a target molecule, and still develop selective nanodetection systems. This review focuses on recent advances regarding the use of gold nanoparticles and nanorods in nuclear medicine. The up-to-date advancements will be shown concerning preparations with special attention on the dimensions and functionalizations that are most used to attain an enhanced performance of gold engineered nanomaterials. Many ideas are offered regarding recent in vitro and in vivo studies. Finally, the recent clinical trials and applications are discussed. gold nanoparticles; gold nanorods; nanoradiocompounds; radiopharmaceuticals; drug delivery; theragnostic; nuclear medicine; nanomedicine +
Footnote †: journal: Medical  
Radiopharmaceuticals are showing amazing outcomes in diagnostic (90%) and therapeutic (10%) applications for many diseases such as cancer, heart and brain diseases, and so on [33]. They consist of a radioactive nuclide linked to a biologically active molecule directed to the target of interest. When radionuclides emit \(\gamma\) rays (either directly, as pure \(\gamma\) emitters, or indirectly, as \(\beta+\) emitters), the radiopharmaceutical is intended for diagnostic imaging. When radionuclides emit \(\beta-\) or \(\alpha\) particles (thanks to the cell-damaging properties) the radiopharmaceutical is used for therapeutic applications and, in some recent research studies, even for radio-guided surgery [34; 35; 36]. Therapostics is a new term that implies the use of the same molecule, labeled with different radionuclides, for both diagnostic and therapeutic purposes [37; 38; 39]. Radiopharmaceuticals have been increasingly used for medical diagnosis since the late 1940s, when nuclear medicine was born. Nuclear medicine aims at evaluating both physiological function as well as biochemical changes in disease conditions; it includes two-dimensional (2D) imaging (planar scintigraphy) and three-dimensional (3D) imaging (single-photon emission computed tomography, SPECT, and positron emission tomography, PET). The functional information obtained by SPECT and PET may need to be coupled with the anatomic/morphologic information typically provided by computed tomography (CT) (hence SPECT and PET are now commonly called SPECT-CT and PET-CT): these approaches, named \"hybrid imaging\", have many advantages as well as high sensitivity, good spatial resolution, and the possibility to correctly locate functional abnormalities (by the SPECT or PET component) within a definite anatomic field (by the CT component) [34]. The \(\gamma\)-emitting radionuclides that are used for planar and SPECT imaging are usually obtained within hospital nuclear medicine facilities (or research departments) from small portable generators; some are produced by nuclear reactors and then shipped to the hospital facility ready to use. The \(\beta+\) emitting radionuclides that are used for PET imaging are sometimes obtained from generators--or, more frequently, from cyclotrons located in industrial sites or in hospitals. PET radionuclides contribute to the higher costs of PET and PET-CT imaging as compared to planar, SPECT, and SPECT-CT imaging. The B-emitting radionuclides deliver highly energetic electrons that release their energy over up to 1 or 2 millimeters (path length) in the adjacent tissues; therefore, they are commonly used for therapeutic purposes (usually called radiometabolic therapy) [40; 41]. Over the past 40 years, the therapeutic potential of several other radionuclides emitting \(\alpha\) particles or Auger electrons has been assessed.