Design of a dual responsive receptor with oxochromane hydrazide moiety to monitor toxic Hg2+ and Cd2+ ions: Usage on real samples and live cells

In this work, we report a facile receptor OMB [N′,N”’-(3-((4-oxochroman-3-yl)methylene)pentane-2,4- diylidene)bis(4-methoxybenzohydrazide)] for the simultaneous detection of toxic analytes (Hg2+ and Cd2+ ions) in environment and biological samples. The receptor OMB exhibits an excellent selectivity and sensitivity which was determined using absorption and emission spectra. The receptor OMB shows rapid detection with lowest LOD (0.62 nM for Hg2+ ions and 0.77 nM for Cd2+ ions) and LOQ (2.08 nM for Hg2+ ions and 2.57 nM for Cd2+ ions) values. In addition, the receptor OMB exhibits 1:1 binding stoichiometry towards Hg2+ and Cd2+ ions with binding constant values of 5.5 × 106 M−1 and 4.6 × 106 M−1. Moreover, the synthesized receptor OMB possess ability to detect these analytes (Hg2+ and Cd2+ ions) in realistic samples (food and water) which was recognized using photoluminescence spectroscopy technique. In addition, the receptor OMB is also utilized to detect both the analytes in live HeLa cells. Thus, the overall results indicate that the receptor OMB was more suitable to detect the toxic analytes (Hg2+ and Cd2+ ions) present in the environment. [Display omitted] •A facile receptor OMB was synthesized based on intra-molecular PET and CHEF effect.•The receptor targets both Hg2+ and Cd2+ ions simultaneously with high sensitivity.•The receptor is able to detect both Hg2+ and Cd2+ ions up to nM levels.•The receptor was used to detect the Hg2+ and Cd2+ ions in real samples.