Nobel Chemistry Prize Goes to Henri Kagan and Kenso Soai for Mirror-Image Chemistry That Amplifies Itself

The third Nobel announcement of China's Golden Week arrived on October 7, when the Royal Swedish Academy of Sciences awarded the 2026 chemistry prize to Henri B. Kagan of Paris-Sud University in France and Kenso Soai of Tokyo University of Science in Japan. The citation, read out in Stockholm and relayed within minutes by Xinhua, honors "the discovery of non-linear effects and autocatalysis in asymmetric organic synthesis." The two laureates split 12 million Swedish kronor — about 8 million yuan, a million more than last year's purse, as Science Net noted.

Their shared subject is the handedness of molecules. Many molecules come in left- and right-handed mirror forms, chemically identical except in how they fit together — and life uses only one hand: every protein on Earth is built from left-handed amino acids. Making single-handed molecules efficiently is also the backbone of pharmaceutical manufacturing, because the wrong-handed twin of a drug can be inert or harmful.

Kagan showed that handedness does not add up proportionally: a catalyst mixture holding only a small excess of one mirror form can pass that bias, exaggerated, to the product — an effect known as asymmetric amplification. Soai supplied the mechanism's most dramatic demonstration. His 1995 reaction is autocatalytic: the product is itself the catalyst that makes more of itself, so a trace of initial handedness grows into near-total dominance. A chemical system, in other words, that reproduces and magnifies its own asymmetry.

That is why the prize resonates beyond industrial chemistry. The Soai reaction offers a laboratory model for how life's one-handedness — homochirality, as chemists call it — might have crystallized out of a primordial world of near-perfect symmetry: a whisper amplified into a rule. Zhihu's front page was asking exactly this within hours of the announcement, what chemical homochirality is and what the two chemists contributed, while Caixin led its international section with the news.

Chinese coverage carried its own small lesson in breaking-news translation. The Paper's first item transliterated Soai's surname as 砚井健三; its second, published the same day, switched to 硤合宪三 — the characters still settling as wire copy crossed the language barrier.

It completes a Nobel week the site has followed from the start: the medicine prize for optogenetics, with China naming its own contenders, then the physics prize that broke a 34-year pattern by going to a single laureate, IceCube's Francis Halzen. Kagan, born in 1930, becomes one of the oldest chemistry laureates in the prize's history; the medals are handed out in Stockholm on December 10.