New Sensor Spots Fish Spoilage Fast

Triethylamine, or TEA, is a chemical that shows up when fish starts to go bad. Detecting it accurately helps people know if the fish is still fresh. Many existing sensors for TEA are not very sensitive, they react slowly, and they need high heat to work.

Researchers have now built a new sensor that joins a polyoxometalate metal‑organic framework with zinc oxide. This heterojunction is the first of its kind for TEA detection. The device works at 140 degrees Celsius, which is lower than many older models.

In tests the sensor gave a strong signal of 64.5 when exposed to 10 parts per million of TEA. It responded in about 49 seconds and recovered in 108 seconds. The material also showed good selectivity and stayed stable for over a month. The junction creates many more active spots on the surface, which helps the reaction.

The team used computer modeling, electrical measurements, and infrared spectroscopy to explain how the sensor works. They then tried it on real crucian carp stored at room temperature and it caught the TEA released as the fish spoiled. This suggests the tool could give a quick freshness check for seafood.