SPL Set ID: 37f8c405-ccb6-4fcd-8513-108956bb1674

11.1 Chemical Characteristics Fluorodopa F 18 Injection is a radioactive diagnostic agent used in PET imaging. The active ingredient 6-[ 18 F] Fluoro-L-3, 4-dihydroxyphenylalanine has the molecular formula of C 9 H 10 FNO 4 with a molecular weight of 214.18, and has the following chemical structure: Fluorodopa F 18 Injection is a sterile, pyrogen-free, clear, colorless solution. Each mL contains between 37 MBq/mL to 1,480 MBq/mL (1 mCi/mL to 40 mCi/mL) of no-carrier added Fluorodopa F 18 (6-[ 18 F] Fluoro-L-3, 4-dihydroxyphenylalanine) at the end of synthesis (EOS). There is 40.88 mg Na-EDTA, 140 mg ascorbic acid, and 663 mg ethanol in 28 mL ±1 mL sodium phosphate buffer. The pH of the solution is between 3 and 5. FDOPA Structure 11.2 Physical Characteristics Fluorine F 18 is a cyclotron produced radionuclide that decays by positron emission to Oxygen O 18 (stable) and has a physical half-life of 109.7 minutes. The principal photons useful for imaging are the dual 511 keV gamma photons, which are produced and emitted simultaneously in opposite direction following positron-electron annihilation (Table 2). Table 2. Principal Radiation Emission Data for Fluoride F 18 Radiation/Emission % Per Disintegration Mean Energy Positron(+) 96.73 249.8 keV Gamma(±) * 193.46 511.0 keV * Produced by positron annihilation 11.3 External Radiation The point source air-kerma coefficient for F 18 is 3.75 × 10 -17 Gy m 2 / (Bq s). The half-value layer (HVL) for the 511 keV photons is 5 mm lead (Pb). The range of attenuation coefficients for this radionuclide as a function of lead shield thickness is shown in Table 3. For example, the interposition of a 9 mm thickness of Pb, with a coefficient of attenuation of 0.25, will decrease the external radiation by 75%. Table 3. Radiation Attenuation of 511 keV Photons by lead (Pb) shielding Shield thickness (Pb) mm Coefficient of Attenuation 0 0.00 5 0.50 9 0.25 15 0.10 29 0.01 39 0.001 52 0.0001 For use in correcting for physical decay of this radionuclide, the fractions remaining at selected intervals after calibration are shown in Table 4. Table 4. Physical Decay Chart for Fluorine F 18 Time Since Calibration Fraction Remaining 0 * 1.000 15 min 0.909 30 min 0.826 60 min 0.683 110 min 0.500 220 min 0.250 440 min 0.060 12 hours 0.011 24 hours 0.0001 * Calibration time 11.1 Chemical Characteristics Fluorodopa F 18 Injection is a radioactive diagnostic agent used in PET imaging. The active ingredient 6-[ 18 F] Fluoro-L-3, 4-dihydroxyphenylalanine has the molecular formula of C 9 H 10 FNO 4 with a molecular weight of 214.18, and has the following chemical structure: Fluorodopa F 18 Injection is a sterile, pyrogen-free, clear, colorless solution. Each mL contains between 37 MBq/mL to 1,480 MBq/mL (1 mCi/mL to 40 mCi/mL) of no-carrier added Fluorodopa F 18 (6-[ 18 F] Fluoro-L-3, 4-dihydroxyphenylalanine) at the end of synthesis (EOS). There is 40.88 mg Na-EDTA, 140 mg ascorbic acid, and 663 mg ethanol in 28 mL ±1 mL sodium phosphate buffer. The pH of the solution is between 3 and 5. FDOPA Structure 11.2 Physical Characteristics Fluorine F 18 is a cyclotron produced radionuclide that decays by positron emission to Oxygen O 18 (stable) and has a physical half-life of 109.7 minutes. The principal photons useful for imaging are the dual 511 keV gamma photons, which are produced and emitted simultaneously in opposite direction following positron-electron annihilation (Table 2). Table 2. Principal Radiation Emission Data for Fluoride F 18 Radiation/Emission % Per Disintegration Mean Energy Positron(+) 96.73 249.8 keV Gamma(±) * 193.46 511.0 keV * Produced by positron annihilation 11.3 External Radiation The point source air-kerma coefficient for F 18 is 3.75 × 10 -17 Gy m 2 / (Bq s). The half-value layer (HVL) for the 511 keV photons is 5 mm lead (Pb). The range of attenuation coefficients for this radionuclide as a function of lead shield thickness is shown in Table 3. For example, the interposition of a 9 mm thickness of Pb, with a coefficient of attenuation of 0.25, will decrease the external radiation by 75%. Table 3. Radiation Attenuation of 511 keV Photons by lead (Pb) shielding Shield thickness (Pb) mm Coefficient of Attenuation 0 0.00 5 0.50 9 0.25 15 0.10 29 0.01 39 0.001 52 0.0001 For use in correcting for physical decay of this radionuclide, the fractions remaining at selected intervals after calibration are shown in Table 4. Table 4. Physical Decay Chart for Fluorine F 18 Time Since Calibration Fraction Remaining 0 * 1.000 15 min 0.909 30 min 0.826 60 min 0.683 110 min 0.500 220 min 0.250 440 min 0.060 12 hours 0.011 24 hours 0.0001 * Calibration time