Sodium iodide (131I) solution
EUROPEAN PHARMACOPOEIA 5.0
Sterility. If intended for parenteral use, it complies with
the test for sterility prescribed in the monograph on
Radiopharmaceutical preparations (0125). The solution
may be released for use before completion of the test.
Iodide. Liquid chromatography (2.2.29).
Test solution (a). The preparation to be examined.
Test solution (b). Dilute the preparation to be examined
with 0.05 M sodium hydroxide until the radioactivity is
equivalent to about 74 MBq/ml. Add an equal volume of
a solution containing 1 g/l of potassium iodide R, 2 g/l
of potassium iodate R and 10 g/l of sodium hydrogen
carbonate R and mix.
RADIOACTIVITY
Determine the radioactivity of the package using a calibrated Reference solution (a). Dilute 1 ml of a 26.2 mg/l solution of
potassium iodide R to V with water R, V being the maximum
instrument.
recommended dose in millilitres.
LABELLING
Reference solution (b). Dilute 1 ml of a 24.5 mg/l solution of
potassium iodate R to V with water R, V being the maximum
The label states any substance added and the number of
recommended dose in millilitres. Mix equal volumes of this
capsules in the package.
solution and of reference solution (a).
IMPURITIES
Blank solution. Prepare a solution containing 2 mg/ml
of each of the components stated on the label, apart from
131
A. [ I]iodate ion.
iodide.
Column :
— size : l = 0.25 m, Ø = 4.0 mm,
01/2005:0281
— stationary phase : octadecylsilyl silica gel for
chromatography R (5 µm),
131
SODIUM IODIDE ( I) SOLUTION
— temperature : maintain at a constant temperature between
20 °C and 30 °C.
Natrii iodidi (131I) solutio
Use stainless steel tubing.
Mobile phase : dissolve 5.844 g of sodium chloride R in
DEFINITION
1000 ml of water R, add 650 µl of octylamine R and adjust to
Solution containing iodine-131 in the form of sodium
pH 7.0 with phosphoric acid R ; add 50 ml of acetonitrile R
iodide and also sodium thiosulphate or some other suitable and mix.
reducing agent. It may contain a suitable buffer.
Flow rate : 1.5 ml/min.
Content :
Detection : spectrophotometer at 220 nm and radioactivity
— iodine-131 : 90 per cent to 110 per cent of the declared
detector connected in series.
radioactivity at the date and hour stated on the label,
Injection : 25 µl ; inject test solution (a), the blank solution
— iodide : maximum 20 µg in the maximum recommended
and reference solutions (a) and (b).
dose in millilitres.
Run time : 12 min.
Relative retention with reference to iodide (retention
PRODUCTION
time = about 5 min) : iodate = 0.2 to 0.3.
Iodine-131 is a radioactive isotope of iodine and may be
obtained by neutron irradiation of tellurium or by extraction System suitability :
— in the chromatogram obtained with the blank solution,
from uranium fission products. No carrier iodide is added.
none of the peaks shows a retention time similar to that
CHARACTERS
of the peak due to iodide,
— resolution : minimum 2 between the peaks due to iodide
Appearance : clear, colourless solution.
and iodate in the chromatogram obtained with reference
Half-life and nature of radiation of iodine-131 : see Table of
solution (b) recorded with the spectrophotometer.
physical characteristics of radionuclides (5.7).
Limit : examine the chromatogram obtained with the
IDENTIFICATION
spectrophotometer; locate the peak due to iodide by
comparison with the chromatogram obtained with reference
A. Gamma-ray spectrometry.
solution (a) :
Results : the spectrum obtained with the preparation to
— iodide : not more than the area of the corresponding peak
be examined does not differ significantly from that of a
in the chromatogram obtained with reference solution (a).
standardised iodine-131 solution. The most prominent
gamma photon has an energy of 0.365 MeV.
RADIONUCLIDIC PURITY
B. Examine the chromatograms obtained in the test for
Iodine-131 : minimum 99.9 per cent of the total radioactivity.
iodide.
Gamma-ray spectrometry.
Results : the principal peak in the radiochromatogram
Determine the relative amounts of iodine-131, iodine-133,
obtained with test solution (a) is similar in retention time iodine-135 and other radionuclidic impurities present.
to the principal peak in the chromatogram obtained with
RADIOCHEMICAL PURITY
reference solution (a).
[131I]Iodide. Liquid chromatography (2.2.29) as described in
TESTS
the test for iodide with the following modification.
Injection : test solution (b).
pH (2.2.3) : 7.0 to 10.0.
RADIOCHEMICAL PURITY
[131I]iodide. Liquid chromatography (2.2.29) as described in
the test for iodide with the following modifications.
Injection : 20 µl of test solution (b) and reference solution (a).
Limit : examine the chromatogram obtained with the test
solution using the radioactivity detector and locate the peak
due to iodide by comparison with the chromatogram obtained
with reference solution (a) using the spectrophotometer :
— [131I]iodide : minimum 95 per cent of the total
radioactivity.
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See the information section on general monographs (cover pages)
EUROPEAN PHARMACOPOEIA 5.0
Sodium iodohippurate (123I) injection
Limit : examine the chromatogram obtained with the
radioactivity detector :
— [131I]iodide : minimum 95 per cent of the total
radioactivity.
RADIOCHEMICAL PURITY
[131I]iodide. Liquid chromatography (2.2.29).
Test solution. Dilute the preparation to be examined with an
equal volume of a solution containing 1 g/l of potassium
iodide R, 2 g/l of potassium iodate R and 10 g/l of sodium
RADIOACTIVITY
hydrogen carbonate R and mix. If necessary, first dilute
Measure the radioactivity using suitable equipment by
the preparation to be examined with a 2 g/l solution of
comparison with a standardised iodine-131 solution or by
sodium hydroxide R to ensure that the final mixture has
using a calibrated instrument.
a radioactivity concentration suitable for the radioactivity
detector.
LABELLING
Reference solution (a). Dissolve 10 mg of potassium
The label states :
iodide R in water R and dilute to 10 ml with the same solvent.
— any substance added,
Reference solution (b). Dissolve 20 mg of potassium
— the maximum recommended dose, in millilitres,
iodate R in water R and dilute to 10 ml with the same solvent.
— where applicable, that the preparation is suitable for use Mix equal volumes of this solution and reference solution (a).
in the manufacture of parenteral dosage forms.
Column :
IMPURITIES
— size : l = 0.25 m, Ø = 4.0 mm,
— stationary phase : octadecylsilyl silica gel for
A. [131I]iodate ion.
chromatography R (5 µm),
01/2005:2121 — temperature : constant, between 20 °C and 30 °C.
Use stainless steel tubing.
SODIUM IODIDE (131I) SOLUTION FOR Mobile phase : dissolve 5.85 g of sodium chloride R in
1000 ml of water R, add 0.65 ml of octylamine R and adjust
RADIOLABELLING
to pH 7.0 with dilute phosphoric acid R ; add 50 ml of
acetonitrile R and mix.
Natrii iodidi (131I) solutio
Flow rate : 1.5 ml/min.
ad radio-signandum
Detection : spectrophotometer at 220 nm and a radioactivity
detector connected in series.
DEFINITION
Strongly alkaline solution containing iodine-131 in the form Injection : 20 µl.
of sodium iodide. It does not contain a reducing agent.
Run time : 12 min.
Content : 90 per cent to 110 per cent of the declared
Relative retention with reference to iodide (retention
iodine-131 radioactivity at the date and hour stated on the
time = about 5 min) : iodate = 0.2 to 0.3.
label.
System suitability : reference solution (b) :
— resolution : minimum 2 between the peaks due to iodide
PRODUCTION
and iodate in the chromatogram recorded with the
Iodine-131 may be obtained by neutron irradiation of
spectrophotometer.
tellurium or by extraction from uranium fission products. No
Limit : examine the chromatogram obtained with the
carrier iodide is added.
radioactivity detector :
CHARACTERS
— [131I]iodide : minimum 95 per cent of the total
Appearance : clear, colourless solution.
radioactivity.
Half-life and nature of radiation of iodine-131 : see Table of
RADIOACTIVITY
physical characteristics of radionuclides (5.7).
Determine the radioactivity using a calibrated instrument.
IDENTIFICATION
LABELLING
A. Gamma-ray spectrometry.
The label states :
Results : the spectrum obtained with the preparation to
be examined does not differ significantly from that of a
— the method of production of iodine-131,
standardised iodine-131 solution. The most prominent
— the vehicle and any substance added,
gamma photon of iodine-131 has an energy of 0.365 MeV.
— that the preparation is not for direct human use.
B. Examine the chromatograms obtained in the test for
radiochemical purity (see Tests).
IMPURITIES
Results : the principal peak in the radiochromatogram
A. [131I]iodate ion.
obtained with the test solution is similar in retention time
to the principal peak in the chromatogram obtained with
01/2005:0564
reference solution (a).
TESTS
Alkalinity (2.2.4). The preparation is strongly alkaline.
RADIONUCLIDIC PURITY
Iodine-131 : minimum 99.9 per cent of the total radioactivity.
Gamma-ray spectrometry.
Determine the relative amounts of iodine-130, iodine-131,
iodine-133, iodine-135 and other radionuclidic impurities
present.
General Notices (1) apply to all monographs and other texts
SODIUM IODOHIPPURATE (123I)
INJECTION
Natrii iodohippurati (123I) solutio iniectabilis
DEFINITION
Sodium iodohippurate (123I) injection is a sterile solution
of sodium (2-[123I]iodobenzamido)acetate. It may contain
a suitable buffer and a suitable antimicrobial preservative
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