Place and achieving a magistral preparation in a service of nuclear medicine: example of the IBZM

The radio-pharmacist is competent and a legal licensee to realizing magistral preparations, defined in the book V of public health Code. We present here the case of a radiopharmaceutical drug prepared extemporary on a medical prescription, the labelling of BZM by iodine 123. The choice of this molecule is made after obtaining the indispensable pre-requisites (lack of noxiousness, teratogenicity, validation by pre-clinic studies, etc). The IBZM allows achieving the etiologic diagnosis of extra-pyramidal syndromes by scintigraphic visualisation of central D2 dopaminergic receptors. The magistral preparation of a radiopharmaceutical implies: (1). Identification of the row materials indispensable in warranting the labelling quality and innocuity of the final injected product. This is done by means of routine chemical reactions, described by France Pharmacopoeia or specifically established. Thus, all the row materials are tested and referenced prior to utilization. (2). The radio-labelling is effected in the day of the examination following a validated procedure: labelling of BZM by sodium iodate in buffer acid medium, extraction of formed IBZM by an organic solvent, purification of IBZM by HPCL, brought in injectable form by chromatographic passage (Sep Pack) and sterilizing filtration. (3). The test of final product is done prior to its injection by measuring the pH and co-elution by HPLC with the cool standard product. The IBZM is delivered providing its radiochemical purity is higher than 90%. A sterility test of preparation is effected a posteriori. The magistral preparation of IBZM allows neurological scintigraphic examinations, still unique in nuclear medicine. Other radiopharmaceuticals with cerebral use will be proposed to clinicians by radio-pharmacists. In all the these cases, the quality of injected labeller will be warranted by the same pharmaceutic approach