Indian scientists design inexpensive biosensor for disease diagnosis

Written by Ayan Ali, Future Science Group

Two scientists from the Indian Institute of Science (Bangalore, India) have devised an economical paper based biosensor detecting lipase, an enzyme routinely investigated in cardiac and liver related diseases.

“Enzymes are one of the important targets of bioanalytes in the field of biosensors as they play crucial roles in the regulation of metabolic functions in living systems. The detection of enzyme activity through an efficient and simple design is, therefore, of utmost importance.”

With the continuing advancement of biosensor technology in clinical applications, Professor Uday Maitra and his student Tumpa Gorai sought to develop an easy to use, portable and inexpensive device that can play an important role in diagnosing various diseases and also helpful in biological and medical science research.

“Our lab has fabricated a low-cost paper biosensor that rapidly detects the presence of lipase, a pancreatic enzyme, which breaks down fats into smaller molecules called fatty acids and glycerol during the process of digestion. While a certain amount of lipase is important for maintaining normal digestive function, an abnormally high level of lipase indicates damage to the pancreas,” the pair commented.

The sensor consists of a paper disc enclosed with a gel named terbium, and doped with an artificial enzyme substrate.  The disc turns green under UV light once it comes in contact with lipase, the intensity of the colour is indicative of the amount of enzyme present.

The gel is amongst many other similar gels developed by Maitra’s labs, which make use of metals that emit light upon photoexcitation.

The device is the first of its kind and holds many promises in the field of point-of-care diagnosis.

“The advantage with this system is that the entire sensing material is integrated on the paper surface in a single step. The material cost for the disc fabrication was calculated to be less than Rs 1, so it is a low-cost luminescent assay system. This simple paper-based sensor is useful for detecting the presence of enzymes in real samples, and for rapid screening of an inhibitor. We are currently expanding the scope of this enzyme assay,”  they added commenting on their findings published recently published in the journal ACS Sensors.

 

Sources: Gorai T, Maitra U. Supramolecular Approach to Enzyme Sensing on Paper Discs Using Lanthanide Photoluminescence. ACS Sens. 1(7), 934–940 (2016); http://www.biospectrumasia.com/biospectrum/news/224622/a-piece-paper-detect-cardiac-liver-diseases-iisc-research