Quality Control

ROTOP QK – DC System

ROTOP Pharmaka GmbH developed the “ROTOP QK – DC System” to assist our clients in implementation of and compliance with the requirements from the current directive “Radiation Protection in Medicine” (German Radiation Protection Ordinance). It was especially designed for quality control of all ROTOP products by means of thin layer chromatography.

All the constituent parts harmonise optimally so that the radiochemical purity of the different technetium kits can be ascertained conclusively with low expenditure of time, personnel and material.

Our field staff will gladly provide help with qualified on-site training.




Why should I monitor quality myself?

(Abstract of the “ROTOP Manual of Quality Control of 99mTc Radiopharmaceuticals”)

99mTc radiopharmaceuticals are brought to their active form only shortly before their use on the patient. The generator eluate from the 99Mo/99mTc generator is added to the kits in the “hot” laboratory. Kits in this context are made up of powder and contain all the constituent parts which, together with the generator eluate, form the completed radiopharmaceutical. Through this labelling process, a chemical reaction occurs which binds the technetium tightly to a sequestration agent or particle (active agent). Further kit constituents are Sn(II) ions and, in some kits, adjuvants and antioxidants. The chemical structure of the formed 99mTc complex determines the biological behaviour, i.e. the distribution, accumulation and elimination of the radiopharmaceutical in the patient.

The multifaceted complex chemistry of technetium enables the examination of various organs with the same radioactive nuclide, 99mtechnetium.

To insure that this step in the formation of the technetium complex succeeds well with a high degree of certainty, every batch is checked under laboratory conditions by the manufacturer of the kits. The manufacturers of the generator and the isotonic saline solution likewise produce and check the products according to all the regulations of reliable pharmaceutical manufacturing.

However, there are several steps which cannot be influenced by the manufacturers:

  • Transport
  • Storage
  • The actual process of labelling

Unsuitable temperatures could occur during transport and storage that could lead to premature ageing of the kits, the saline solution and the generators. During the labelling process, which takes place in your laboratory, several errors can occur, mostly unwittingly, that could lead to incomplete labelling.

It is imperative that patients be protected from unnecessary radiation exposure. Misuse must therefore be eliminated wherever possible.

The impurities that emerge during the labelling process are mainly “free” pertechnetate 99mTcO4- (as in the generator eluate) and reduced hydrolysed 99mTc (colloidal 99mTc). A certain small amount of impurities is naturally unavoidable. The acceptable level is defined in the European Pharmacopoeia (Ph. Eur.) and/or in the instructions for use and expert information for the individual kits. It is specified as a percentage of radiochemical purity (e.g. minimum of 95 % for 99mTc DTPA) or as an impurity limit (e.g. not exceeding 5.0 % for 99mTc microspheres).



ROTOP-Fibel zur Qualitätskontrolle von 99mTc-Radiopharmaka (ROTOP Manual of Quality Control of 99mTc Radiopharmaceuticals), Astrid Gräfe, Dresden, April 2011, first edition, © 2011 ROTOP Pharmaka AG, 01328 Dresden, Germany

All rights reserved, especially the rights of reproduction, distribution and translation. Published by: ROTOP Pharmaka AG, 01328 Dresden, Germany