Technetium (99mTc) Medronate Complex Injection
Technetium (99mTc) MDP Complex Injection; (99mTc) Dihydrogen Methylene Diphosphonate (MDP) Complex Injection
Category. Diagnostic
Description. A clear, colourless aqueous solution. Technetium (99mTc) MedronateMDP Injection; (99mTc) Dihydrogen
Methylene Diphosphonate (MDP) Complex Injection
Description: A clear, colourless aqueous solution. Technetium (99mTc) MDP Complex Injection is a sterile solution of
sodium methylene diphosphonate (sodium medronate) that is complexed with technetium-99m, in presence of a
stannous salt or other suitable reducing agent. The injection is suitable for intravenous administration and contains
sufficient sodium chloride to make the solution isotonic with blood.
Technetium (99mTc) MDP Complex Injection contains not less than 90 per cent and not more than 110 per cent of the
stated technetium-99m radioactivity at the date and time stated on the label. Not less than 95 per cent of the total
technetium-99m radioactivity is present as technetium (99mTc) MDP complex.
Radiopharmaceutical preparation. Technetium (99mTc) Medronate Complex Injection is prepared aseptically
following manufacturer’s instructions provided with the kit. The kit contains sodium sodium methylene diphosphonate
(sodium medronate) and a stannous salt. The kit may have preadjusted pH and may contain reducing, chelating,
stabilizing, filling and antioxidizing agents as well as antimicrobial preservatives and buffers. The injection may also be
prepared under aseptic processing combined with sterilization by filtration. Sodium pertechnetate 99mTc (fission or nonfission), complying with specification given for it, is used with the kit to make the ( 99m Tc) Pentetate Injection.
Identification
A. Determine by gamma-ray spectrometry. The spectrum obtained corresponds to the spectrum obtained with reference
solution of technetium-99m. The most prominent gamma photon of technetium-99m has energy of 0.140 MeV.
B. In the test for Radiochemical purity, the chromatogram obtained contributes to the identification of the distribution
of radioactivity in the preparation.
Tests
pH (2.4.24). 5.0 to 8.0.
Radioactivity assay: Radioactivity of an aliquot of Test Solution is assayed using pre-calibrated radioactivity dose
calibrator as described in measurement of radioactivity in general chapter on Radiopharmaceutical preparation. It is
expressed as MBq (mCi) in volume V ml at a particular time and date.
Radionuclidic purity. Not less than 99.9 per cent due to: Technetium-99m (99mTc)
Complies with the radionuclidic purity tests as described under monograph on Sodium pertechnetate (99m)Tc injection
(fission) or Sodium pertechnetate (99m)Tc injection (non-fission) used for preparation of Technetium (99mTc) MDP
Complex Injection
Radiochemical purity.
Method A. Determine by ascending paper chromatography (2.4.15).
Mobile phase. 0.5 M acetate buffer adjusted to pH 5.
Apply 2 to 5 µl of the test solution at 3 cm above the bottom of the strip on Whatman No.1 paper strip (3cm X 23cm).
The Rf value for 99mTc Pertchnetate is 0.6 to 0.7, Rf value for Technetium (99mTc) MDP Complex is 0.8 to 1 and Rf
value for reduced hydrolysed 99mTc is 0.
The percentage of activity due to technetium-99m MDP i.e. activity under Rf zone of 0.8 to 1.0, shall be not less than 90
per cent of the total activity on the paper.
Method B: Determine the RCP of the injection by paper chromatography.
Support: chromatography paper Whatman No.1;
Solvents: 85 % methanol, acetate buffer (0.5M; pH~5)
Spot about two to five microlitres of 99mTc-MDP with a capillary or a micropipette at the point of spotting marked at 3
cm from one end of the strip (3 x 23 cm) in duplicate.
Develop the chromatogram by ascending chromatography in both the solvents till the solvent front reaches 15 cm from
the point of spotting. This takes about 90 min and about 60 min in 85 % methanol and acetate buffer (0.5M; pH~5)
respectively. Allow the strips to dry.
Scan the strips using a radiochromatogram scanner with collimator suitably adjusted to measure 99mTc or cut into one
cm sections and count in a well type NaI(Tl) scintillation counter. % of Impurities viz. free pertechnetate and reduced
hydrolysed technetium are determined in the solvents, viz. 85 % methanol (R f 0.55– 0.75) and acetate buffer (Rf 0.00.1) respectively as follows:
(%) free pertechnetate = Activity in the [99mTc] pertechnetate zone x 100
Total Activity
(%) reduced hydrolysed technetium = Activity in RHT zone x 100
(RHT)
Total Activity
Percentage of each impurity shall be not more than 5 % of the total activity.
The radiochemical purity of Tc-MDP = 100 – (% free pertechnetate + % reduced hydrolysed technetium)
The RCP shall not be less than 90% of the total activity.
Biodistribution: Carry out the test as described under (…) using a set of three wistar rats. Inject a volume less than 0.2
ml containing not more than 200µg (0.2mg) of MDP. Determine the radioactivity in the liver and kidney. Biodistibution
pattern shall not be less than 2% in both femurs, not more than 5% in liver and not more than 5% in kidneys of Total
Retained Dose (% TRD) in 2 out of 3 rats
Sterility Complies with the test for sterility as described in general chapter on Radiopharmaceutical preparation. The
injection may be released for use before completion of the test.
Bacterial endotoxins Less than 175/V EU/mL V being the maximum recommended dose in mL.
Storage: Store at room temperature with adequate shielding. Use within 6h of time of preparation
Labelling— The label states, in addition to the information specified under injections (1) the amount of 99mTc as total
megabecquerels (millicuries) and concentration as megabecquerels (millicuries) per ml at the time of calibration (2) the
expiration date (3) the statement “Caution—Radioactive Material.”