IISc Develops Glowing Sensor for Liver Cancer Diagnosis

The glowing paper sensor is made using terbium, a rare earth metal that helps in detecting β-glucuronidase, an enzyme linked to liver cancer conditions.

Indian Institute of Science (IISc) scientists have developed a glowing paper sensor for early detection of liver cancer, utilizing the green glow of a rare earth metal called terbium.

Leveraging the unique photophysical properties of terbium, this sensor targets β-glucuronidase, an enzyme intricately linked to multiple pathological conditions, including liver cancer.

Beta-glucuronidase, which normally helps break down glucuronic acid, also serves as a key biomarker for cancers such as colon, breast, and kidney, and even infections and AIDS.

Elevated levels of this enzyme are also associated with neonatal jaundice and NSAID-induced toxicity.

Ananya Biswas, a former PhD student and co-author of the study published in Chemistry said, “Traditional detection methods often struggle with background noise or low sensitivity, but terbium has a unique ability - it glows for longer periods, helping to cut through the noise and get a clearer signal.”

The IISc team started by studying how certain metal ions form gels. They found that when terbium ions were added to a gel made from bile salts, the mixture gave off a bright green glow.

To make the technology accessible, the team embedded the gel matrix onto paper discs, thereby creating a simple and portable sensor. When exposed to samples containing -β-glucuronidase, these discs emit a pronounced green glow under UV light.

Unlike expensive lab equipment, this sensor can be read using a simple UV lamp and free software called ImageJ, making it ideal for low-resource settings, IISc said. The sensor can detect enzyme levels as low as 185 nanograms per millilitre, well below the levels usually seen in serious liver disease.