(131I) Meta-Iodobenzyl Guanidine Injection for Therapeutic Use
Iobenguane Injection for Therapeutic Use
Category. Therapeutic.
Description. A clear, colourless or slightly yellow solution. On standing the solution may darken as a result of
the effect of radiation.
(131I) Meta-Iodobenzyl Guanidine Injection for Therapeutic Use is a sterile, apyrogenic solution of 1(3-[131I] iodobenzyl) guanidine or its salts. It may contain a suitable buffer, a suitable labelling catalyst such as
ionic copper, a suitable labelling stabiliser such as ascorbic acid and antimicrobial preservatives.
(131I) Meta-Iodobenzyl Guanidine Injection for Therapeutic Use contains not less than 90.0 per cent
and not more than 110.0 per cent of the stated iodine-131 radioactivity at the date and time stated on the label.
Not less than 95 per cent of the radioactivity corresponds to iodine-131 in the form of Meta-Iodobenzyl
Guanidine. The specific radioactivity is not less than 400 GBq of iodine-131 per gram of iobenguane base.
Iodine-131 has a half-life of 8.04 days and emits beta and gamma radiation.
Identification
A. Determine by gamma-ray spectrometry. The spectrum obtained corresponds to the spectrum obtained with the
reference solution of Iodine 131. The most prominent gamma photon of iodine-131 has energy of 0.365 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. Measure the radioactivity using a suitable counting apparatus or by measurement in an
instrument calibrated with the aid of such a solution.
Radionuclidic purity. Not less than 99.9 per cent due to iodine-131.
Determine by Gamma-ray spectrometry.
The most prominent gamma photon of iodine-131 has energy of 0.364 MeV.
Radiochemical purity. Examine by liquid chromatography (2.4.14).
Test solution. The injection under examination.
Reference solution (a). A 0.1 per cent w/v solution of sodium iodide in the mobile phase.
Reference solution (b). A 0.02 per cent w/v solution of iobenguane sulphate RS in the mobile phase.
Chromatographic system
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a stainless steel column 25 cm x 4.0 mm, packed with silica gel (5 µm),
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mobile phase. mixture of 1 volume of 8.0 per cent w/v solution of ammonium nitrate, 2 volumes of
dilute ammonia and 27 volumes of methanol,
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flow rate. 1.0 ml per minute,
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a suitable radioactivity detector,
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a spectrophotometer set at 254 nm,
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injection volume 10 µl
Inject the test solution, reference solution (a) and (b). In the chromatogram obtained with the test solution not less
than 92 per cent of the radioactivity of the chromatogram is found in the peak corresponding to iobenguane. Not
more than 7 per cent of the radioactivity is found in the peak corresponding to iodide and not more than 1 per
cent of the radioactivity is found in other peaks.
Sterility (2.2.11). 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 (2.2.3). Less than 175/V IU/ml, V being the maximum volume of injection.
Storage: Store frozen at < 0oC with adequate shielding.
Labelling. The label states in addition to the information specified under injections (1) the amount of 131I 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.”