New Catalyst was Discovered to Ease the Drug labeling Process

Posted by Alex Brown on January 26th, 2016

Scientists from USA found an iron catalyst for drug isotope labeling with fewer steps involved while keeping the cost much lower, as iron, the source material of the catalyst, is common in Nature.

Studying drugs’ performance in vivo and in vitro is an important part for drug discovery and development, and the characters of drug will be learned mainly for their ADME activities. To ensure no disruption will influence the real activities of the drug compound, isotopic labeling is widely employed in related studies with no change of the drug compounds’ structure and other chemical and physical characters. And usually, radioactive isotope compounds were employed to achieve the tracing job, in which ¹⁴C and ³H are mostly contained.

The conventional method to label the compound with isotopes assisting by iridium or rhodium is complicated while being both time and cost consuming. The newly developed iron catalyst can help to directly achieve the labeling process of tritium (³H) within only one step.

With the new iron catalyst, hydrogen can be directly exchanged with its isotope of tritium, and then finish the step of labeling, besides, under the catalysis of iron, the ³H isotopes can spot the C-H bonds that are available for the replacement, expanding the labeling rate in this way.  Further benefit of the new catalyst is that the source of the tritium can be its gas form, saving the inconvenience to prepare other forms of ³H for the labeling.

The iron catalyst is radioactive labeling friendly also because it brings less waste during the process for that it can react under a low tritium pressure and in the common solvents that drug molecules are stored. And the last but not the least, iron is widely existing in the world, thus the cost of it will be much cheaper than its counterparts.

The performance of the iron catalyst was firstly inspected in stable isotope labeling of drug molecule with non-radioactive isotopes of hydrogen. Positive results were showed in the experiment, after which, scientists conducted radioactive labeling to inspect its ability resulting in efficient and wide functions.

At present the research team is planning to make the new catalyst commercially available soon for isotope labeling needs will benefit greatly from its good performance in various aspects.

The finding was co-made by the Department of Chemistry, Princeton University and Merck Research Laboratories, and the paper was named Iron-catalysed tritiation of pharmaceuticals published on the Journal of Nature with the DOI number being 10.1038/nature16464.