Barry Sharpless, Nobel Laureate in Chemistry 2001 and 2022 (middle) with Dr Wenjie Liu (right). Professor Sharpless, is one of only five scientists in in history to win a Nobel Prize twice, in 2001 for 'his work on chirally catalysed oxidation reactions', and in 2022 for 'for the development of click chemistry and bioorthogonal chemistry'. Photo: Dr W Liu