China’s high school chemistry experiment using aspirin tablets failed because they switched to using domestically produced tablets. This news made it to the top of Baidu’s hot search list on January 21st.
According to mainland Chinese media on January 20th, in the second year of high school chemistry in China, there was an ester base test experiment using aspirin tablets (with acetylsalicylic acid as the active ingredient). Before the hydrolysis of acetylsalicylic acid, it did not change color when it encountered ferric chloride. However, after the hydrolysis of acetylsalicylic acid to produce salicylic acid, the solution turned purple when it encountered ferric chloride.
In early January, a chemistry teacher at a renowned high school in Beijing, Cao Kui, revealed that from 2020 to 2021, they used Bayer’s (a German pharmaceutical company) enteric-coated aspirin tablets, and the experimental results were normal. But due to the expensive price of Bayer’s enteric-coated aspirin tablets, starting from 2023, Cao Kui’s school began using domestically produced aspirin tablets from companies like Chenxin Pharmaceutical and Shiyao Group as experimental materials. As a result, the solution changed color before and after hydrolysis, making it impossible to compare pre- and post-hydrolysis as before.
In early January 2025, Cao Kui conducted the above experiment using domestically produced enteric-coated aspirin tablets from several different manufacturers in Beijing, Nanjing, Shenyang, etc., most of which had passed the national consistency evaluation. However, the experiment results showed that tablets from different manufacturers all changed color, with varying intensities, where the darker the color, the higher the salicylic acid content.
A senior pharmacist from a well-known Grade A hospital in Beijing stated that the content of free salicylic acid in enteric-coated aspirin tablets to some extent reflects the product’s quality.
As salicylic acid can cause adverse reactions such as nausea, vomiting, gastric ulcers, and even gastric perforation, the design of acetylating salicylic acid to produce acetylsalicylic acid by a chemist named Hoffman working at Bayer in 1897 was a significant development. In 1899, Bayer named this acetylsalicylic acid as aspirin. In 1993, Bayer introduced enteric-coated aspirin tablets that do not dissolve in the stomach when stimulated by stomach acid, but dissolve upon reaching the small intestine, further reducing the side effects of aspirin on the stomach.
The news has sparked discussions among netizens. User “Bullet Falling in Love with Gun” said, “We should not thank this great chemistry teacher.”
User “Carbon Pencil” mentioned, “The color change of domestically produced tablets indicates the presence of salicylic acid, meaning it starts hydrolyzing as soon as it enters the stomach, unlike Bayer’s design which delays the release until the drug reaches the intestine for absorption, avoiding gastric irritation. Taking domestically produced tablets can lead to severe side effects, damaging the stomach.”
User “Past Like Wind” expressed concerns about the decrease in drug quality despite the reduction in prices, arguing that drug bidding processes should involve quality inspections to ensure only effective and safe products are selected.
User “Even Dreams Will Smile” analogized with the example of beef mixed with soy protein to highlight the importance of maintaining quality in pharmaceuticals, suggesting that lowering prices at the expense of efficacy compromises healthcare.
User “Integrity First” emphasized the importance of quality over price when it comes to treating the same illness, stating a preference for expensive drugs with better efficacy and fewer side effects.
These reports emerged shortly after the announcement of the results of the tenth batch of China’s centralized drug procurement at the end of December last year. The procurement results indicated the largest historical price reduction, with drug prices at historic lows, averaging over a 70% decrease, including over 90% reductions for multiple products, with enteric-coated aspirin tablets being procured at three cents per tablet.
Recently, at the Shanghai “Two Sessions” held by the Chinese Communist Party, CPPCC member and Chief General Surgeon at Shanghai Ruijin Hospital, Zheng Minhua, expressed concerns over the instability in drug quality due to the low prices of centrally procured drugs, leading to issues like ineffective treatments, anesthesia failures, and laxatives not working. Physicians faced with patient reactions and doubts were feeling helpless as they lacked the choice or channels to address these concerns.
Lu Changlin, a CPPCC member and Chief of Cardiology at Beijing Chaoyang Hospital, also raised concerns at a recent Beijing CPPCC meeting, citing adverse reactions from centrally procured drugs, such as allergic responses, indicating issues with drug purity and manufacturing processes.