Indian Scientists Develop Fluorescent Sensor for Rapid Nicotine Detection

In a development that could strengthen public health screening and biomedical research, scientists at the Institute of Nano Science and Technology (INST), Mohali, have developed a tiny fluorescent “turn-on” sensor capable of rapidly detecting nicotine and cotinine, its major metabolite, in water-based media as well as in living cells. The innovation may help enable faster and earlier detection of nicotine exposure, including the long-lasting biological footprint left by cotinine.

According to the Ministry of Science and Technology, the need for such a sensor is significant because smoking and exposure to second-hand smoke continue to pose major global health risks. While nicotine is the addictive chemical associated with tobacco use, cotinine remains a more stable biomarker that can be detected in blood, saliva and urine, making it especially useful for monitoring tobacco exposure and studying nicotine metabolism.

The new sensor is based on an iron metal-organic framework, or Fe-III-MOF, designed in the form of microscopic nanospheres. Researchers said the material contains tiny pores that can trap nicotine-related molecules. These Fe-MOF nanospheres were synthesised through a solvothermal process and then tested for safety and performance.

Using intracellular imaging and confocal microscopy, the scientists observed that when nicotine or cotinine molecules entered the pores of the nanospheres, the material glowed more brightly and shifted toward a blue fluorescence. The study, published in the journal Nanoscale, found the nanospheres to be highly selective and recyclable, with researchers attributing the fluorescence enhancement to host-guest interactions and electron transfer that produce a stronger emission signal.

Researchers say the iron-based material offers several advantages for biological applications because iron is abundant, the system is simple to operate, it functions in aqueous media, and it shows low cytotoxicity with high biocompatibility. These properties could make it useful for non-invasive health monitoring, screening for smoking exposure, studies on addiction and metabolism, and the future development of low-cost sensing kits for broader diagnostic use.

The ministry added that the fluorescent MOF-based platform could eventually be adapted for detecting other biomarkers as well, opening the door to wider medical and public health applications beyond nicotine monitoring.

Source: PIB