Meldal, Morten P.

Morten P. Meldal, (born January 16, 1954, Denmark), Danish chemist whose research into the synthesis of peptides and other organic compounds contributed to the development of click chemistry, in which simple, quick, high-yielding reactions are used to make functional biomolecules. Meldal was known in particular for his work on copper-catalyzed azide-alkyne cycloaddition (CuACC), a highly efficient chemical reaction in click chemistry, which he developed simultaneously and independently of American chemist K. Barry Sharpless. The discovery of the CuACC reaction opened up new opportunities in research and development, especially in the areas of materials science and pharmaceutical development. For his discoveries, Meldal was awarded a share of the 2022 Nobel Prize in Chemistry, which he shared with Sharpless and American chemist Carolyn R. Bertozzi.

Meldal attended the Technical University of Denmark (DTU), where he studied chemical engineering, focusing specifically on the synthesis of oligosaccharides and graduating with a Ph.D. in 1983. He subsequently studied peptide synthesis as a postdoctoral researcher at the MRC Laboratory of Molecular Biology at the University of Cambridge and, later, at the University of Copenhagen. In 1996 he returned to DTU, becoming a professor there. Two years later he accepted a professorship at the University of Copenhagen, where in 2011 he became a professor of nanochemistry at the Nano-Science Center.

Meldal’s early research centred on peptide synthesis, with particular interest in developing methods to discover novel pharmaceutical compounds. To do so, he generated libraries of molecules that could be screened for activity against potential therapeutic targets. In the process of those studies, Meldal observed an unusual reaction between two chemical groups, an azide and an alkyne. He realized that the reaction had been controlled by copper ions, such that only a single reaction product had been formed, leaving no unwanted by-products. The reaction subsequently became known as CuACC. As the prototypical click reaction, it works by joining two different molecules via the introduction of an azide in one molecule and an alkyne in a second molecule; following the addition of copper ions to the reaction, chemists are able to snap the two different molecules together. CuACC has numerous applications, including in the synthesis of new organic compounds, in medicinal chemistry and pharmaceutical development, and in surface and polymer chemistry.

Meldal was also known for having pioneered various techniques and methods to improve peptide synthesis. Notably, his innovations involving polyethylene glycol (PEG)-based resins and fluorescence-based screening contributed to significant advances in combinatorial solid phase technology. He also developed a novel optical encoding technique, known as microparticle matrix (MPM) encoding, in which PEG-based resins were used to facilitate the direct identification of structures in molecular libraries. The technique was especially valuable for the study of relationships between peptide structure and bioactivity.