Packaging and storage
Preserve in a single-dose container that is adequately shielded.
Labeling
Label it to include the following, in addition to the information specified for
Labeling under
Injections 1: the time and date of calibration; the amount of
15O as water expressed as MBq (mCi) per mL, at time of calibration; total activity at time of calibration; the expiration time and date; and the statement CautionRadioactive Material. The labeling indicates that in making dosage calculations, correction is to be made for radioactive decay and also indicates that the radioactive half-life of
15O is 2.03 minutes. The label also includes the statement, Do not use if cloudy or if it contains particulate matter.
Identification
A:
Radionuclidic identityIts half-life, determined using a suitable detector system (see
Radioactivity 821), is between 1.83 and 2.08 minutes.
B:
Radiochemical identityThe retention time of the major peak in the chromatogram of the
Test solution corresponds to that of the water contained within the product formulation, as obtained in the test for
Radiochemical purity.
Radiochemical purity
The gas chromatograph (see
Chromatography 621) is equipped with thermal conductivity and radioactivity detectors and a 0.53-mm × 30-m column coated with a film of G16 stationary phase. The column temperature is maintained at 40
, and the injector and detector temperatures are maintained at 250
and 200
, respectively. The carrier gas is helium, flowing at a rate of about 10 mL per minute. Inject about 50 µL of the Injection into the chromatograph, record the chromatogram, and measure the responses for the major peaks of both the radioactive and the nonradioactive detection systems (the volume of Injection being adjusted, if necessary, to obtain suitable detection system sensitivity): the column efficiency determined from the analyte peak is not less than 10,000 theoretical plates; the tailing factor for the analyte peak is not more than 1.5; and the relative standard deviation for replicate injections is not more than 5%. Not less than 95% of the radioactivity is Water O 15, and the retention time of the Water O 15 corresponds to the retention time of the water contained within the product formulation.
Radionuclidic purity
Using a gamma-ray spectrometer (see
Selection of a Counting Assembly under
Radioactivity 821), count an appropriate aliquot of the Injection for a period of time sufficient to obtain a gamma spectrum. The resultant gamma spectrum should be analyzed for the presence of identifiable photopeaks which are not characteristic of
15O emissions. Not less than 99.5% of the observed gamma emissions should correspond to the 0.511 MeV, 1.022 MeV, or Compton scatter peaks of
15O.
Chemical purity
This article can be synthesized by different methods and processes and, therefore, may contain different impurities. The presence of unlabeled ingredients, reagents, and by-products specific to the process must be controlled, and their potential for physiological or pharmacological effects must be considered.
Other requirements
It meets the requirements under
Injections 1, except that the Injection may be distributed or dispensed prior to completion of the test for
Sterility 71, the latter being started within 24 hours of final manufacture, and except that it is not subject to the recommendation for
Volume in Container.
Assay for radioactivity
Using a suitable calibrated system as directed under
Radioactivity 821, determine the radioactivity of the Injection, in MBq (or mCi) per mL.