technetium tc 99m sodium pertechnetate - Medications

Sodium Pertechnetate Tc 99m Injection, as eluted according to the elution instructions with Lantheus Medical Imaging, Inc. TECHNELITE ® , Technetium Tc 99m Generator, is in 0.9% Sodium Chloride Injection, USP as a sterile, non-pyrogenic, diagnostic radiopharmaceutical suitable for intravenous injection and direct instillation. The pH is 4.5-7.5. The eluate should be clear, colorless, and free from visible foreign material. Each eluate of the TECHNELITE ® , Technetium Tc 99m Generator should not contain more than 0.0056MBq (0.15 microcuries) of Molybdenum Mo99 per 37MBq (1 millicurie) of Technetium Tc 99m per administered dose at the time of administration, and not more than 10 micrograms of aluminum per milliliter of the Technetium Tc 99m Generator eluate, both of which must be determined by the user before administration. Since the eluate does not contain an antimicrobial agent, it should not be used later than one (1) working day after the elution (12 hours). Lantheus Medical Imaging, Inc. TECHNELITE ® , Technetium Tc 99m Generator consists of a column containing uranium fission produced Molybdenum Mo99 adsorbed on alumina. The terminally sterilized and sealed column is enclosed in a lead shield; the shield and other components are sealed in a cylindrical plastic container with an attached handle. Built into the top surface are two recessed wells marked SALINE CHARGE and COLLECT. Needles protruding from these two wells accommodate supplied sterile eluant charge vials and sterile eluate collection vials. The eluting solvent consists of 0.9% Sodium Chloride Injection, USP, prepacked into septum-sealed vials, to make the solution isotonic. The eluate collection vial is evacuated, sterile and non-pyrogenic. A sterile 0.22 micrometer bacteriological filter is incorporated between the column outlet and the collection vials. During and subsequent to elution, the eluate collection vial should be kept in a radiation shield. The Generator is shipped with a silicone needle seal over the charge needle and a vented needle cover over the collect needle. A sterile collect needle seal is supplied for the customer to aseptically reseal the collect needle after each elution. Physical Characteristics Technetium Tc 99m decays by isomeric transition with a physical half-life of 6.02 hours. 1 Photons that are useful for imaging studies are listed in Table 1. Table 1. Principal Radiation Emission Data - Technetium Tc 99m Radiation Mean %/Disintegration Mean Energy (keV) Gamma-2 89.07 140.5 External Radiation The specific gamma ray constant for Technetium Tc 99m is 5.4 microcoulombs/Kg-MBq-hr (0.795 R/mCi-hr) at 1cm. The first half-value thickness is 0.023cm of lead (Pb). To facilitate control of radiation exposure from millicurie amounts of Technetium Tc 99m, for example, the use of a 0.27 cm thick standard radiation elution lead shield will attenuate the radiation emitted by a factor of about 1000. A range of values for the relative attenuation of the radiation emitted by this radionuclide that results from interposition of various thicknesses of lead is shown in Table 2. NOTE : Because the generator is well contained and essentially dry, there is little likelihood of contamination due to damage in transit. Table 2. Radiation Attenuation of Technetium Tc 99m by Lead Shielding Shield Thickness lead (Pb) cm Coefficient of Attenuation 0.023 0.5 0.09 10 -1 0.18 10 -2 0.27 10 -3 0.33 10 -4 Molybdenum Mo99 decays to Technetium Tc 99m with a Molybdenum Mo99 half-life of 66 hours. This means that only 78% of the activity remains after 24 hours; 60% remains after 48 hours, etc. (see Table 3). All units have a minimum of 38 mm, 1.5 inches (~ 6 half-value layers) of lead surrounding the activity. (See Table 3.) Table 3. Molybdenum Mo99 Decay Chart Half-Life 66.0 Hours Days Percent Remaining Days Percent Remaining 0 100 10 8 1 78 11 6 2 60 12 5 3 47 13 4 4 37 14 3 5 28 15 2 6 22 20 0.6 7 17 25 0.2 8 13 30 0.05 9 10 The physical decay characteristics of Molybdenum Mo99 are such that approximately 88% of the decaying Molybdenum Mo99 atoms form Technetium Tc 99m. Since the Molybdenum Mo99 is constantly decaying to fresh Technetium Tc 99m, it is possible to elute the generator at any time. However, the total amount of Technetium Tc 99m available will depend on the time interval from the previous elution, the quantity of Molydenum Mo99 remaining and the efficiency of the elution. Approximately 47% of maximum Technetium Tc 99m is reached after 6 hours and 95% after 23 hours. The elution vial shield has a wall thickness of 7.9 mm, 0.31 inches, and reduces transmitted Technetium Tc 99m radiation essentially to zero. To correct for physical decay of Tc 99m, the fractions that remain at selected intervals of time are shown in Table 4. Table 4. Physical Decay Chart: Technetium Tc 99m Half-Life 6 Hours *Calibration Time Hours Percent Remaining Hours Percent Remaining 0* 100.0 9 35 1 89 10 32 2 79 11 28 3 71 12 25 4 63 14 20 5 56 16 16 6 50 18 13 7 45 24 6 8 40

The Ultra-Technekow ™ V4 Generator is prepared with fission-produced molybdenum Mo-99 adsorbed onto alumina in a column shielded by lead, tungsten, or depleted uranium. The column assembly and shielding are encased in a plastic container that is covered with a plastic elution hood. The elution hood has an opening for the column assembly double inlet needles and an opening for the single outlet needle. The needles accommodate the sterile eluant vials that contain 0.9% Sodium Chloride Injection and sterile evacuated collection vials. A sterile vial containing a bacteriostat is supplied with the generator for the customer to aseptically seal the outlet needle after each elution. This terminally sterilized generator provides a closed system for the production of sterile metastable technetium Tc-99m, which is produced by the decay of molybdenum Mo-99. Incorporated between the column outlet and the collection vial is a sterile 0.22 micrometer filter. Sterile, non-pyrogenic isotonic solutions of Sodium Pertechnetate Tc 99m Injection in 0.9% Sodium Chloride Injection can be obtained conveniently by periodic aseptic elution of the generator. These solutions should be clear, colorless, and free from any particulate matter. The Sodium Pertechnetate Tc 99m Injection is suitable for intravenous injection and direct instillation. The carrier-free solution may be used as is, or diluted to the proper concentration. Over the life of the generator, an elution will contain an amount of technetium Tc-99m in direct proportion to the quantity of Mo-99 decay since the previous elution of the generator. The quantity of Tc-99m in the eluate is determined by quantity of Mo-99 on the column, and the elapsed time between elutions. Each eluate of the generator should not contain more than the USP limit of 0.15 kilobecquerel molybdenum Mo-99 per megabecquerel technetium Tc-99m (0.15 microcurie Mo-99 per millicurie Tc-99m) per administered dose at the time of administration and an aluminum ion concentration of not more than 10 micrograms per milliliter of the generator eluate, both of which must be determined by the user before administration. Since the eluate does not contain an antimicrobial agent, it should not be used after 12 hours from the time of generator elution. Physical Characteristics Technetium Tc-99m decays by isomeric transition with a physical half-life of 6 hours. The principal photon that is useful for detection and imaging studies is listed in Table 1. Table 1. Principal Radiation Emission Data Radiation Mean Percent Per Disintegration Energy (keV) Gamma-2 89.07 140.5 External Radiation The specific gamma ray constant for technetium Tc-99m is 0.795 R/hr-mCi at 1 cm. The first half-value layer is 0.023 cm of lead (Pb). A range of values for the relative attenuation of the radiation emitted by this radionuclide that results from interposition of various thicknesses of Pb is shown in Table 2. For example, the use of 0.27 cm thickness of Pb will attenuate the radiation emitted by a factor of about 1000. Table 2. Radiation Attenuation by Lead Shielding Shield Thickness (Pb) cm Coefficient of Attenuation 0.023 0.5 0.09 10 -1 0.18 10 -2 0.27 10 -3 Molybdenum Mo-99 decays to technetium Tc-99m with a molybdenum Mo-99 half-life of 2.75 days, or 66 hours (see Table 3). The physical decay characteristics of molybdenum Mo-99 are such that only 88.6% of the decaying molybdenum Mo-99 atoms form technetium Tc-99m. Generator elutions may be made at any time, but the amount of technetium Tc-99m available will depend on the interval measured from the last elution. Approximately 47% of the maximum available technetium Tc-99m is reached after 6 hours and 95% after 23 hours. To correct for physical decay of molybdenum Mo-99 and technetium Tc-99m, the fractions that remain at selected intervals of time are shown in Tables 3 and 4. Table 3. Physical Decay Chart; Molybdenum Mo-99, Half-Life 66 Hours Days Percent Remaining Days Percent Remaining 0 100 10 8 1 78 11 6 2 60 12 5 3 47 13 4 4 37 14 3 5 28 15 2 6 22 20 0.6 7 17 25 0.2 8 13 30 0.05 9 10 Table 4. Physical Decay Chart; Technetium Tc-99m, Half-Life 6 Hours Hours Percent Remaining Hours Percent Remaining 0* 100 9 35 1 89 10 32 2 79 11 28 3 71 12 25 4 63 14 20 5 56 16 16 6 50 18 13 7 45 24 6 8 40 *Calibration Time