| Objective To synthesise a novel"on/off"type rhodamine fluorescent probe by structural modification of rhodamine derivatives with chromone-3-carbaldehyde,2-hydroxy-1-naldehydes and pyridoxal phosphate,to investigate the performance and influence conditions of the fluorescent probe and to detect zinc ions in zinc gluconate tablets and aluminium ions in water using the fluorescent probe.The results are presented in the following sections.The new fluorescent probes were used for the synthesis of new fluorescent probes and for the detection and application of zinc and aluminium ions.Methods Three novel structures of rhodamine fluorescent probes were designed and synthesized by organic synthesis.After the structures were determined,the properties and conditions of the three probes were examined by UV and fluorescence spectroscopy,using the characteristic"open-close"type of probe,i.e.the spirolactam structure of the rhodamine fluorescent probe emits no fluorescence in the closed-loop state and opens when reacting with a specific metal,resulting in a change in fluorescence and solution colour of the whole system.The accuracy,precision and linearity of the probes for the detection of metals were examined using methodological investigations of the linearity of the probes and metal ions for the detection of zinc ions in zinc gluconate and aluminium ions in water.Results Three fluorescent probes were synthesised and the characteristic absorption peaks of the UV spectra were used to confirm that the systems Y2ST-Zn2+,LPDQ-Zn2+and NJQ-Al3+,respectively,had been successfully constructed.The detection limit of Y2ST was 0.77×10-6mol/L,and the linearity was good at 5×10-6-5×10-5mol/L for the determination of Zn2+with a recovery of 94.6-95.8%,which can be used for the determination of Zn2+.The detection limit of LPDQ was 0.8×10-6mol/L.The linearity was 93.7-95.5%for the determination of Zn2+at 1×10-5-8.5×10-5 mol/L,which can be used for the determination of Zn2+.The detection limit of NJQ was 0.4×10-6mol/L,and the linearity was good in the range of 5×10-6-5×10-5mol/L for the determination of Al3+with a recovery of 93-95.4%,which can be used for the determination of Al3+.Conclusions The Y2ST probe has good selectivity and reversibility for the detection of Zn2+and is better than the LPDQ probe,but the Y2ST probe needs to be dissolved in dichloromethane for detection,so the range of substances that can be detected is narrower than that of the LPDQ probe for the detection of Zn2+.The LPDQ probe has good selectivity for the detection of Al3+in water samples and can be used for cellular imaging of Heal cells,which enhances the usefulness of the probe. |
