Presentation on theme: "1 Life Analytical Chemistry-Molecular Imaging (MI): Nuclear Imaging Gaolin Liang, Ph. D. Professor, Ph. D. Advisor Deptartment of Chemistry University."— Presentation transcript:
1 Life Analytical Chemistry-Molecular Imaging (MI): Nuclear Imaging Gaolin Liang, Ph. D. Professor, Ph. D. Advisor Deptartment of Chemistry University of Science and Technology of China
2 By Wei Huang, Ph.D. candidate Stanford University
4 Nuclear Imaging PET SPECT Fusion techniques: PET/CT Fusion techniques: SPECT/CT Practical concerns in nuclear imaging The amount of radiation from diagnostic nuclear medicine procedures is kept within a safe limit and follows the "ALARA" (As Low As Reasonably Achievable) principle.
9 Physiologic distribution of [18F]-FDG After i.v. injection, [18F]-FDG is distributed in the body like glucose. In accord with the glucose consumption of the cells, it is taken up by the glucose transport proteins, mainly by the GLUT-I, and phosphorylyzed by the hexokinase. Unlike glucose, [18F]-FDG does not take part in further steps of the glucose metabolism, which leads to a trapping of the molecule in the cells. Due to increased anaerobic glycolysis, many tumor cells show an up regulation of GLUT-I and of hexokinase, which together with physiologic trapping leads to an accumulation of FDG. [18F]-FDG is mainly excreted by the kidneys. In normal tissues, [18F]-FDG does not show a uniform distribution. The most intense physiologic uptake is seen in brain tissue, which is diagnostically used for a wide range of indications in neurology and psychiatry.
22 1 mL K 222 /K 2 CO 3 (15 mg/ml & 3 mg/ml in 9:1 ACN/H 2 O) drying 4-5 mg precursor, 1 ml anhydrous DMSO, 120 °C for 20 min Add 10 mL H 2 O, C 18 cartridge, wash once with 5 mL H 2 O 3 mL ACN (with 50 μL Bu 4 NOH) to rinse the cartridge 20 mg TSTU, 90 °C for 10 min HPLC purify, R t : 23.4-24.4 min (7-37min: 5 – 65 % ACN) C 18 cartridge, wash it once (5 mL H 2 O) 1 mL ACN rinse the cartridge ( 18 F-SFB) Typical peptide labeling (Lys side chain): 10 mCi 18 F-SFB + 0.4 mg peptide Total time: 1 h Decay-corrected yield: 30-60% (5-10 peptides) Typical protein labeling (Lys side chain): 10 mCi 18 F-SFB + 0.4 mg protein Total time: 30-40 min Decay-corrected yield: 1-30% (3- 5 proteins) Procedure