Radiopharmaceutical positron-emitting

The apphcations described here illustrate the wide range of uses for robotic systems. This chapter is not intended to he exhaustive there are many other examples of successful applications, some of which are referenced below. For instance, Brodach et al. [34] have described the use of a single robot to automate the production of several positron-emitting radiopharmaceuticals and TTiompson et al. [3S] have reported on a robotic sampler in operation in a radiochemical laboratory. Both of these apphcations have safety imphcations. CHnical apphcations are also important, and Castellani et al. [36] have described the use of robotic sample preparation for the immunochemical determination of cardiac isoenzymes. Lochmuller et al. [37], on the other hand, have used a robotic system to study reaction kinetics of esterification. 

The most useful and important positron emitting radiopharmaceuticals, 2-deoxy-2-[ F]fluoro-D-deoxyglucose [ F]FDG, is prepared in a two-step... 

Another study was undertaken to determine the prevalence of adverse reactions to positron-emitting radiopharmaceuticals through a prospective 4-year study in 22 institutions. PET radiopharmaceuticals have an excellent safety record because no adverse reactions were reported in over 80 000 administered doses in this study (3). 

Silberstein EB. Prevalence of adverse reactions to positron emitting radiopharmaceuticals in nuclear medicine. Pharmacopeia Committee of the Society of Nuclear Medicine. J Nucl Med 1998 39(12) 2190-2. 

Nuclear medicine - in particular, positron emission tomography (PET) - is one of the emerging, important fields of practical application of iodonium salts. PET is a powerful and rapidly developing area of molecular imaging that is used to study and visualize human physiology by the detection of positron-emitting radiopharmaceuticals [50-55], PET experiments provide direct information about metabolism, receptor/enzyme... 

PET imaging is performed with positron emitting radiopharmaceuticals. After collision of the emitted positrons with electrons, pairs of gamma-rays are formed that are detected by the PET camera. The most important PET tracer is F-Fludeoxyglucose ( F-FDG) with a physical half-life of 110 min. F-FDG is nowadays synthesised by nucleophilic substitution of the precursor mannose triflate using fully automated synthesis procedures and cyclotron-produced F-fluoride ions. After purification the resulting... 

Phelps, M. E. 1978. ECAT—New computerized tomographic imaging-system for positron-emitting radiopharmaceuticals. J. Nucl. Med. 19 635-647. 

The main feature of the short-lived positron-emitting isotope F is the relative long half-life of 110 min. The ultrashort-lived isotopes C, N, and O have half-lives of 2-20 min, and they must subsequently be produced in the vicinity of the PET scanner(s). Radiopharmaceuticals labeled with F, on the contrary, can be shipped to distant satellite PET centers that are notequippedwith a cyclotron. Several commercial companies are today producing 2-[ F]fluoro-2-deoxy-D-glucose... 

PET Radiopharmaceuticals PET radiopharmaceuticals are labeled with shortlived positron-emitting radionuclides. Such radionuclides can either be produced in a cyclotron or obtained from an appropriate radionuclide generator. 

Some Positron Emitters of Clinical Interest Fluorine-18 is undoubtedly the most widely used positron-emitting radionuclide. This is mainly due to the wide use of 18FDG, the PET radiopharmaceutical that has permitted PET to become an everyday clinical tool. With the exception of 18FDG and probably 18FDOPA, the use of other 18F-labeled radiopharmaceuticals is very limited. However, the chemical and physical characteristics of 18F are excellent ... 

Carbon-11 has a very short half-life (just 20.4min) but the chance to substitute a carbon atom in any biological molecule by a positron-emitting nC is a very interesting possibility. This has led to a substantial development of nC-labeled tracers. The short half-life conditions everything and only PET centers equipped with a cyclotron can have a chnical program with nC tracers. The production of the radiopharmaceutical must in these cases be performed just before the imaging study and is usually not started until the patient is already on the PET scanner. 

A PET radiopharmaceutical laboratory must include the cyclotron bunker (where positron-emitting radionuclides are produced), the production laboratory, the quality control laboratory, and several different ancillary areas. 

Positron emitting nuclides have very short half lives, on the order of minutes to tw o hours. This makes operation of a cyclotron and a radiochemistry laboratory essential to the use of PET scanners. is the longest radionuclide with a half-life of 1.87h, making a central production facility within a city feasible for radiopharmaceuticals employing this nuclide. Most clinical PET facilities have on-site cyclotrons and radiopharmaceutical laboratories to allow the use of short-lived isotopes in clinical studies. 

C-Labelled phosgene is a useful material in radiopharmaceutical and nuclear medical applications, since it combines the radiophysical properties of C with the extensive reaction chemistry of phosgene to permit the rapid synthesis of a wide range of biologically-active materials with radiochemical labels. Carbon-11 is a short-lived positron-emitting radionucleide, useful for in vivo measurements with positron emission tomography (PET) [519], Because of... 

Triflate 133 has been used94 in the course of the synthesis of 4-[18F]fluoroproline 134 according to the reaction scheme in equation 62. Positron-emitting [18F]fluorine (t1/2 = 109.7 min), a very attractive isotope used for labelling radiopharmaceuticals, has been... 

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