Terminalia chebula: a novel natural product colorimetric sensor for Fe2+ and Fe3+ ions

Abstract

Natural product like Terminalia chebula as Fe2+ and Fe3+ ions sensor was not reported in the literature till now. Herein, we first reported Terminalia chebula (T. chebula), a natural product used in Ayurveda, as a highly sensitive, simple, and cost-effective colorimetric sensor for the detection of Fe2+ and Fe3+ ions. Terminalia chebula showed a selective colorimetric sensing ability for iron (2+/3+) by changing color from green and pale yellow to blue, having limit of detection level of 43.7 μM and 60.8 μM for Fe2+ and Fe3+ ions, respectively. The concentration-dependent colorimetric determination of iron (2+/3+) was carried out, and the color change to distinguish between different concentrations was excellent. Using High Performance Liquid Chromatography, the fraction having sensing ability was isolated and purified. From the mass spectra of the purified fraction, it was concluded that, the major component responsible for the sensing ability was tri-O-galloyl-β-D-glucose. This chemosensor could be used to detect and quantify Fe2+ and Fe3+ in water samples, which is particularly a useful tool.