A simple uracil-appended uorescent sensor (1) has been developed by one pot reaction and characterized by using common spectroscopic methods such as UV-vis, Fluorescence, HRMS and FT-IR spectroscopies. Upon addition of various metal ions to the CH 3 CN solution of sensor 1, the uorescence was quenched in the presence of Cu 2+ / Hg 2+ ions. The limit of detection for Cu 2+ and Hg 2+ was calculated to be 3.31 and 0.316 µM, respectively. Further, the sensor was applied for real-life applications in the determination of Vitamin B 2 (ribo avin) and its presence in milk products. On the incorporation of different sources of vitamin-B to acetonitrile solution of it, there was discernible uorescence enhancement only in the presence of vitamin B 2 . Also, it has been successfully applied for the detection of Vitamin B 2 (ribo avin) in milk and curd. Moreover, based on the uorescent color changes, the sensor was utilized for invisible ink applications.