Highly chemoselective turn-on fluorescent probe for ferrous (Fe2+) ion detection in cosmetics and live cells

In modern society, the use of cosmetics has increased extensively; unfortunately, so-called several toxic metal salts are present as the colorant or filler in cosmetics. The ferrous ion (Fe2+) is one of the metal ions used in cosmetics as a colorant. Ferrous ion (Fe2+) is a vital component in live cells. Considering the adverse effect of high doses of ferrous ions in cosmetics and live cells, we developed a turn-on fluorescent probe P-Fe(II) for quantitative estimation of ferrous ion (Fe2+) in cosmetics and monitoring of labile ferrous (Fe2+) ion in live cells. The fluorescent probe P FeaD showed a visual color change from colorless to orange in the presence of ferrous ion (Fe2+) in the cosmetics. We observed that UV-absorption increased at 390 nm upon incubation with ferrous ion (Fe2+). The probe P-Fe(II) has provided quantitative information on ferrous ion (Fe2+) in various cosmetics, kajol, lip balm, face foundation, mascara, eyeliner, lipliner, face makeup, sindoor, lipstick, nail polish in ppm level through the fluorescence signaling at 460 nm.The probe P-Fe(II) provided information on labile Fe2+ ion pool via a fluorescence imaging. It is a new addition to the diagnostic inventory for detecting ferrous ion in live cells and cosmetics.