Our unit works with and produces a number of different chemicals and composites.
FluorodeoxyglucoseFluorodeoxyglucose is a glucose analog. Its full chemical name is 2-fluoro-2-deoxy-D-glucose, commonly abbreviated to FDG.
FDG is most commonly used in a Positron Emission Tomography (PET) medical imaging modality. The fluorine in the FDG molecule is chosen to be the positron-emitting radioactive isotope fluorine-18, to produce 18F-FDG. After FDG is injected into a patient, a PET scanner can form images of the distribution of FDG around the body. The images can be assessed by a nuclear medicine physician or radiologist to provide diagnoses of various medical conditions.
FDG, as a glucose analog, is picked up by high-glucose-using cells such as brain, kidney, and cancer cells, where phosphorylation prevents the glucose from being released intact. The 2-oxygen in glucose is needed for further glycolysis, so that (in common with 2-deoxy-D-glucose) FDG cannot be further metabolized in cells, and therefore the FDG-6-phosphate formed does not undergo glycolysis before radioactive decay. As a result, the distribution of 18F-FDG is a good reflection of the distribution of glucose uptake and phosphorylation by cells in the body.
Fluoro DOPAThe dopaminergic system plays a role in motor and cognitive functions (Parkinson's disease) and psychiatric disorders (schizophrenia, depression, addiction) in the brain. The action of the endogenous dopamine neurotransmitter takes place within the dopaminergic neurons, which innervate the forebrain. The neurons are located in two nuclei in the brainstem, the substantia nigra and the ventral tegmental area.
From these areas the neurons are able to project to several other areas in the brain. Dopamine is formed by hydroxylation and decarboxylation of L-tyrosine. After its synthesis in the cytoplasm, dopamine can be released in the synapse through vesicles. This occurs as it binds to postsynaptic dopamine receptors, resulting in formation of second messengers. The action of the neurotransmitter is terminated by absoprtion in the presynaptic nerve terminals through the dopamine absoprtion site (dopamine transporter, DAT). Otherwise, dopamine may be partly metabolized in the synaptic cleft.
Since the first PET-study of dopamine metabolism in the human brain with 6-[18F]fluoro-L-3,4- dihydroxyphenylalanine (6-[18F]FDOPA) , this PET tracer has been extensively used for investigating presynaptic function in brain disorders. From three different ring fluorinated analogues of L-3,4-dihydroxyphenylalanine (LDOPA), 6-[18F]FDOPA was selected as the most potent tracer for PET because of a relatively low affinity for catechol-O-methyltransferase and a relatively high affinity for aromatic amino acid decarboxylase. 6-[18F]FDOPA is furnished by a direct electrophilic radiofluorination followed by HCl-hydrolysis for deprotection and HPLC separation using a physiological phosphate buffer.
CholineCholine labeled with Carbon-11 is a promising biomarker for tumor imaging using PET. It has been shown that there is an increased synthesis of membranal phosphatidylcholinein tumor cells that is correlated with high uptake of this radiopharmaceutical in malignant tissues. It is particularly effective in imaging tumors localized in the brain, lung, esophagus, rectum, prostate and urinary bladder. In contrast to [F-18]fluorodeoxyglucose (FDG), absorption of [C11] choline in benign structures, such as the brain, heart and urinary tract is negligible, resulting in a higher target to background signal ratio for tumors located near those benign structures.
[C-11]Choline is prepared by a [C-11]methylation reaction of dimethylaminoethanol (DMAE) using labeled methyl iodide (MeI), and a simple sep-pak purification step. Therefore, it is very important to determine the quantity of DMAE accurately in the final product.
RacloprideCarbon-11-raclopride was used by PET to successfully assess changes in endogenous dopamine concentration after pharmacological intervention in the living baboon brain. Carbon-11 is synthesized via C-11 methylation and its reaction with des-methyl-raclopride in dimethylsulfoxide.
Acetate[C-11] acetate is another imaging marker for cancer diagnosis. Acetate metabolism in tumors is not yet completely understood, however, it has been suggested that there is a nonoxidative pathway through which acetate enters the lipid pool in the cell. Its accumulation in tumor cells seems to be caused by the low oxygen consumption and enhanced lipid synthesis of these cells
Other PET imaging agents with are produced routinely: FCHOLINE, FLT and FLUORIDE.