Goan scientist helps create simple paper strip test to spot chemicals in seconds

Panaji: Imagine there is a dangerous chemical on a surface. People need to know about it quickly so they can stay safe. But detecting such chemicals usually needs costly machines and trained experts.

Researchers at CSIR-Central Leather Research Institute have found a new way to quickly detect very dangerous chemicals. The study was published in the international journal, Chemistry – A European Journal, led by Amit Vernekar, a scientist of Goan origin from Sanquelim, along with his student Huidrom Mangalsana.The team worked with a special material called Ce-BTB-MOL. Though it was already known to react with chemicals, the scientists discovered something new: it can act like an artificial enzyme that breaks down very harmful chemicals quickly.“This enzyme is called a phosphotriesterase nanozyme, meaning it can break down dangerous organophosphate compounds,” Vernekar said.Harmful chemicals belong to a group called organophosphates. Some of them, like parathion and paraoxon, were once used as pesticides but are now known to be extremely toxic affecting the brain and nerves, and even small amounts can be dangerous.“Parathion, first developed in 1947, has been banned in most countries due to its severe health risks, including links to cancer and birth defects.

Paraoxon, which forms when parathion breaks down in the body, is considered even more dangerous — about 50 times more toxic — and has been associated with chemical warfare programmes in the past. Because these substances can severely affect the human nervous system and may prove harmful depending on exposure, rapid and accurate detection of the same is critical,” he said.The new method therefore, makes things much easier.The scientists created a simple paper strip test. When a drop containing the harmful chemical touches the strip, it changes colour almost immediately, from light to a strong orange-brown. This starts in about 13 seconds and becomes clearer within half a minute.This clear colour change solves a big problem. Earlier tests were confusing because both the chemical and the testing material looked similar in colour.

Now, the difference is easy to see.“The system is highly sensitive, capable of detecting very small amounts of the chemical. The colour intensity can even be measured using a smartphone, making it portable, affordable, and suitable for real-world use. Importantly, the nanozyme can also distinguish between closely related chemicals, which is otherwise difficult with known methods, and is not easily affected by other common substances, ensuring reliable surface contamination testing,” Vernekar further said.According to Vernekar, the team is now trying to make the system even better. They want to detect even smaller amounts of harmful chemicals and get results in just a few seconds.