Application Of Fluorescence Probe Method In The Detection Of Heavy Metal Pollutants

Purpose It is of great significance to metal ions because metal contaminants in the environment can cause serious potential harm to human health and ecological safety.Therefore,in this study,novel fluorescent probes were designed and synthesized to achieve highly selective detection of metal ions in the environment and cell imaging.Methods Based on the good photochemical characteristics of rhodamine B,different recognition groups were grafted onto rhodamine B to construct fluorescent probes.By using the ring opening mechanism of rhodamine B spirolactame induced by metal ion,the target metal ion could be specifically detected.The standard curve and limit of detection for the target metal ion were obtained by fluorescence titration.The Job’s plot study was utilized to explore the binding ratio between probe and the target metal ion.Finally,application of probes in cell imaging was analyzed by fluorescence imaging technology.Results By grafting 2-hydroxybenzoyl hydrazide and naphthalimide derivatives on the rhodamine B matrix,two fluorescent probes P1 and P2 were successfully constructed.In ethanol-water solution（8:2,v:v,p H7.0,20 m M HEPES）and ethanol,P1/P2 selectively recognized Hg²⁺/Al³⁺with“off-on”optical switching respectively,no significant spectral changes were observed toward other metal ions and anions.The limit of detection（LOD）was obtained as low as 0.33μM of Hg²⁺and 0.67μM of Al³⁺,as well as an excellent linearity of 1.0～20.0μM and 2.0～16.0μM,respectively.And also the coordination mode with 1:1 stoichiometry was proposed between P1/P2and Hg²⁺/Al³⁺.It was also demonstrated that the established method had a good recovery for detecting Hg²⁺content in water and P1/P2 could be used as an excellent fluorescent chemosensor for the measurement of Hg²⁺/Al³⁺in living cells with satisfying results.Conclusion Two novel fluorescent probes P1 and P2 were constructed,which could specifically recognize Hg²⁺and Al³⁺respectively with good anti-interference performance.Meanwhile,it displayed potential value in the detection of Hg²⁺in water and the imaging of Hg²⁺and Al³⁺in living cells.The research results will provide references for the design of novel fluorescent probes in the future.