Tc-99m radiopharmaceuticals and in-house chromatographic methods
Posted: 20 November 2019 | Anastasia Petropoulou (University Hospital Bristol’s NHS Foundation Trust) | No comments yet
Technetium-99m (99mTc) is a synthetic radioisotope that is used worldwide to produce radiopharmaceuticals that are mainly used for diagnostic purposes in nuclear medicines. The purity of the final radiopharmaceutical (99mTc-R) can be confirmed by applying chromatographic methods. This method is based on different rates of movement of substances in a sample solution through a porous medium under the influence of a reagent (either a solvent or gas). Anastasia Petropoulou explores some chromatographic techniques used to identify impurities in radiopharmaceuticals based on 99mTc.
Radiopharmaceuticals and their use
The term radiopharmaceutical as it is accepted today covers over a hundred simple and complex radioactive chemicals used in in vivo diagnostic/therapeutic applications and for in vitro clinical diagnostic tests. They are defined as radionuclidic/labelled compounds intended for administration for therapeutic or diagnostic purposes.1 The European Pharmacopoeia mandates that all radioactive pharmaceuticals must be sterile, apyrogenic, free from extraneous particles and of a suitable pH. In addition, radioactive injections must be of the correct radiochemical and radionuclidic purity and have the correct radioactivity present at the stated time of injection. An unacceptable radiochemical purity (RCP) can lead to the radioactivity localising in an unintended target, which may result in organ damage.2 For this reason, the administrative departments of the health ministry responsible for pharmaceutical substances insist that radiopharmaceutical products should be subject to control and must satisfy the purity criteria laid down by the pharmacopoeia commissions aiming to protect public health.1