IISc develops new methods to detect blood sugar
Bengaluru: It may soon be easier to detect diabetes, a disease that keeps around 7% of India away from sweets, at an early stage. The Indian Institute of Science, Bangalore has developed two new methods of testing glucose levels in blood, which could predict the onset of the disease better than existing diagnostic tests.
“To detect glucose (blood sugar), hospitals use chemical-based methods that are complicated and time-consuming. With the ever increasing demand for cheaper, quicker, and more accurate medical diagnostic devices, these technologies may well develop into usable products,” said Ajay Sood, professor of physics at IISc, who is also a fellow of the Royal Society, London.
The research team used two devices which made it possible to sense glucose at a concentration of two nanomolars.
“This is like searching for four people from a population that is 10 times that of India, and catching them,” said Sood. Two other scientists, Prof S. Asokan from the Department of instrumentation and applied physics and and Prof S. Sampath from the department of inorganic and physical chemistry at IISc , are also part of the team.
The International Diabetes Federation estimates that the number of diabetics in the country could go up from 65 million now to 110 million by 2035.
“Most of the patients come at a very late stage and a large part of population also goes undiagnosed. The later the diagnosis, the more the complications on organs like heart, eyes, brain, kidney and liver. In fact, sometimes, patients come to know of diabetes only after they have suffered a heart attack or have an unhealed wound or an eye infection. Early detection tests can reduce the diabetes burden to a large extent,” said Dr Ravi Sankar Erukulapati, Endocrinologist and national lead at Apollo Sugar Clinics.
At present, two standard tests are used for oral glucose tolerance, which indicate what the sugar level is before and after having food. There is another HbA1C (glycated haemoglobin) test, which shows how the sugar levels have been over the past three months.
IISc’s new approach to detect the disease is based on two devices called field effect transistor and Bragg grating. The former is based on electrical signals and the latter uses the principles of optics, Sood said.
Both these methods use what is called functional graphene, a layer of carbon atoms held together. Graphene has a love-hate relationship with water, which makes it repel as well as spread over it. This, in turn, makes graphene attach to glass fibre. This principle makes the test easy and helps detect early onset of the disease.
The other device, based on the principles of wave length, is sensitive enough to detect glucose in an ocean of healthy blood, and can detect glycated haemoglobin, Sood said.