A novel rhodamine phosphorus derivative as fluorescent and colorimetric sensor for highly selective detection of Fe3+ in solution

Based on Rhodamine moiety, a novel phosphorus fluorescent sensor as 2-(6-(diethylamino)-2-((diphenylphosphoryl) methyl)-3-oxo-3-3H-xanthen-9-yl) benzoic acid (ROAP) is firstly designed and synthesized for the detection of Fe3+ in solution. The recognition effect of ROAP sensor is investigated carefully in dimethyl sulfoxide-water (DMSO-H2O) (fw = 70%) dispersion system. Fe3+ ion can lead to the quenching fluorescence and fading color of ROAP sensor. The as-prepared ROAP sensor shows high sensibility, selectivity, and anti-interference for Fe3+ in the concentration range of 0–5 equivalents. The recognition mechanism of the sensor is attributed to the combination of Fe3+ ions with the ROAP sensor via O atoms of PO and OH groups. The stoichiometric ratio of ROAP and Fe3+ complexation is 2:1. The probe also exhibits good reversibility, and high potential commercial applications in the future. [Display omitted] •A phosphorus fluorescent molecule ROAP is constructed from Rhodamine dye firstly.•ROAP molecule has AIE effect in DMSO-H2O solvent.•The as-prepared ROAP sensor shows excellent specificity for detecting Fe3+ by fluorescent and colorimetric approach.•The sensor has high sensitivity and wide detection range.•The stoichiometric ratio of ROAP with Fe3+ is confirmed as 2:1.