Context: This year Nobel Prize in Chemistry 2022 was awarded jointly to Carolyn R. Bertozzi, Morten Meldal and K. Barry Sharpless "for the development of click chemistry and bioorthogonal chemistry".

• The three have been awarded for their work in ‘click chemistry’, in which molecules snap together fast and firmly, without the need for a long, complicated process and too many unwanted byproducts. 

• Their work has applications in the field of medical science, including the treatment of cancer.

What is click chemistry?

• Click chemistry refers to a collection of organic reactions that proceed rapidly and selectively under mild conditions to covalently link molecular components.

• Click reaction uses only readily available reagents and is insensitive to oxygen and water. This aspect makes it widely acceptable.

• Click chemistry is not a single specific reaction, but describes a way of generating products that follow examples in nature, which also generates substances by joining small modular units. 

• Chemists often try to recreate complex chemical molecules found in nature, and this has applications, among other things, in the field of medicine – how to target and block pathogens in cells. However, this process can be complicated and time-consuming.

Applications of Click Chemistry

• Drug discovery: Click chemistry has found increasing applications in all aspects of drug discovery in medicinal chemistry, such as for generating lead compounds through combinatorial methods.

• Bioconjugation: Click chemistry is rigorously employed in proteomics and nucleic research via bioconjugation.

• Radiochemistry: In radiochemistry, selective radiolabeling of biomolecules in cells and living organisms for imaging and therapy has been realized by click reactions.

• Nanoparticle modification: Click chemistry is generally used to conjugate the ligands, folate groups to the nanoparticles, which are then used for nanoparticle drug delivery.

Key significance of their research

• Barry Sharpless and Morten Meldal are awarded the Nobel Prize in Chemistry 2022 because they brought chemistry into the era of functionalism and laid the foundations of click chemistry. 

• They share the prize with Carolyn Bertozzi, who took click chemistry to a new dimension and began using it to map cells. Her bioorthogonal reactions are now contributing to more targeted cancer treatments, among many other applications.

• To simplify, Sharpless came up with the term ‘click chemistry’ and worked extensively on it, Meldal, independently of Sharpless, came up with a special chemical structure called ‘triazole’ which has many significant applications, and 

• Meldal through his experiments came up with the useful chemical structure called triazoles, whch are stable and are found in pharmaceuticals, dyes and agricultural chemicals, says the Nobel website. He also found that the reaction he used could bind together numerous different molecules.

• Bertozzi, using the work of Sharpless and Meldal, came up with an efficient and innovative method to map glycans, which are carbohydrate-based polymers made by all living organisms.

• Bertozzi took the next step of developing click reactions that could work inside living organisms — ‘bioorthogonal’ reactions (a term she coined), take place living systems without interfering with native biochemical processes.