Four years ago, scientists Shantikumar V Nair and Manzoor Koyakutty of Amrita University's Kochi-based Centre for nanomedicine were using lasers to detect contaminants in food.The signals that came from the material, based on principles of Raman spectroscopy, showed distinct patterns, and Nair thought why not bounce laser off human tissue to detect abnormal cells like cancer.The result today is a technology that enables cancer detection in less than 30 minutes without a hospital visit.This will enable early diagnosis and treatment that are vital for curing several forms of the disease. The technology uses a laser with a nano substrate to detect pre-cancerous and cancerous cells.Use of laser to read the nature of cells is not new, but the signals that have been found to be weak and difficult to analyze. The nano substrate (a nano material) placed on the tissue solved the problem.“The nano substrate amplifies the signals and helps us analyse the results. For each type of tissue -nor mal, pre-cancerous and cancerous, there is a distinct Raman spectrum emitted by the laser,“ said Nair, one of the three inventors of the technology .“We used the method on samples of oral cancer, normal tissues and pre-cancerous tissues. The first set of positive results came two years ago,“ said Nair.Having identified the technology , the research team is working on developing a hand-held instrument to detect oral cancer.The department of biotechnology has provided Rs 60 lakh to design it, and the scientists estimate the product, which will cost about Rs 10 lakh, will be ready in two years.“Raman signal helps identify organic molecules in tissues. Since these molecules vary depending up on the condition of the cells, signals coming from cancer tissue with those coming from normal tissue will be distinct,“ said Nair.The equipment will include a Raman nano-sensor to get an amplified signal from the tissue. The signals can be analyzed at a central facility, and the result will be available within 30 minutes.While this is a preliminary test to detect cancer, scientists say it gold standard tests will have to confirm it.Nair, who is also the dean of research at Amrita University , said that the new gadget will enable community level large-scale screening without having to take tissue biopsies.“In principle it can diagnose any cancer from which Raman Spectra can be obtained. This includes skin cancer, or internal cancers if the laser is delivered through optical fibre and the Raman signals are received through the same fibre.“We have paid more attention to oral cancer because of the possibility of screening for these cancers early and also because oral cancer is on the rise and is curable if detected early ,“ Nair said.