A smarter way to detect a toxic pesticide 

Once widely used to treat fungal infections of bananas, wheat, rice and other crops, the fungicide carbendazim is now banned in many countries. Research has found it to be a potential carcinogen and endocrine disruptor in humans, and toxic to many other species, even at extremely small doses. Banning a chemical, however, is only part of the solution. Effective enforcement depends on the ability to detect tiny amounts of the chemical in foods, water and soil.  

Now, a reliable and ultrasensitive electrochemical sensor for detecting carbendazim has been developed by a team led by Matteo Chiesa, Professor of Mechanical and Nuclear Engineering at Khalifa University, working with scientists from Taiwan and India.  

“Ultrahigh sensitivity can be achieved with an extremely straightforward process.”  

Matteo Chiesa

While traditional analytical techniques such as high-performance liquid chromatography can detect pesticide residues, the electrochemical sensor is simpler, more cost-effective and could be incorporated into portable devices, says Chiesa.  

“This sensor can monitor carbendazim contamination in food and the environment, helping farmers, food safety agencies, water authorities, and consumers,” he says.  

Electrochemical sensors work by measuring the small electric current generated by a chemical reaction. In this case, the sensor uses an electrode made of strontium-based vanadate, SrV₂O6, which catalyses the oxidation of carbendazim, generating an electrical current. The SrV₂O6 is combined with MCM-41, a porous silica material that increases the surface area, and the number of electrochemically active sites and sensitivity. The result is a remarkably low detection limit of 1 µg/L.  

What’s more, SrV₂O6 can be very easily synthesised, says Chiesa, using a simple co-precipitation method, which is eco-friendly and cost-effective. “Ultrahigh sensitivity can be achieved with an extremely straightforward process,” he says. 

The sensor is also highly specific for carbendazim. “Even when other similar chemicals are present, it showed strong selectivity, differentiating carbendazim from structurally similar compounds and other potentially interfering substances,” he says. 

The team have tested the sensor’s selectivity and accuracy by measuring trace amounts of carbendazim in apple, coconut, grape, carrot, tomato, cabbage, alluvial soil, sandy soil, peaty soil, tap water, fish water, and human urine. ​ 

“The sensor demonstrated long-term stability, repeatability, and reproducibility, features critical for real-world deployment,” says Chiesa.

The new sensor could be integrated into portable devices for field testing and minaturized and multiplexed for detecting multiple contaminants simultaneously. “Future possibilities include extending this approach to detect other pesticides or toxins using similar composite sensors and preparation routes,” he says.

Reference

Velraj, A., Sivaji, S.P., Chen, S-M., Bharath, G., Chiesa, M. & Liu, J-T. Fruitful design of novel SrV₂O₆@MCM-41-based electrochemical sensor for carcinogenic carbendazim detection in complex real-world matrices. Composites Part B: Eng. 300, 112475, 2025. | Article