Inspired by ancient medical books, the extraction method was found. In the initial experiment, the effect of Artemisia annua was not brilliant, and the search for Tu Youyou was once deadlocked. She looked through the ancient literature again, and several words in "Emergency Recipe for Treating Cold, Heat and Malaria Elbow" caught her attention: "Hold Artemisia annua once, dye it with two liters of water, wring the juice and take it all." It turns out that there is Artemisia annua juice in Artemisia annua, and its use is different from the decoction method commonly used in traditional Chinese medicine, which makes Tu Youyou realize that temperature may be the key to extraction. She used ether with lower boiling point to prepare Artemisia annua extract at 60 degrees Celsius, which was successful.
The inhibition rate of plasmodium reached 100%.
197 1 10 Tu Youyou observed in the laboratory that the inhibition rate of Artemisia annua extract extracted by the new method on plasmodium reached 100%. 1972 in March, Tu Youyou reported the experimental results at the "523 Project" working conference held in Nanjing. 1973, the antimalarial effect of Artemisia annua crystal was confirmed in Yunnan, so the office of "523 Project" decided to name Artemisia annua crystal artemisinin as a new drug for research and development.