Synthesis And Characterization Of A FRET-based Ratiometric Fluorescent Probe For Detection Of Perborate Ion

Fluorescent probes with high selectivity, high sensitivity and can be used toidentify the naked eye, etc., among the more widely used in various fields, es peciallyin the selective detection of various ions and small molecules. The general applicationof fluorescent probes are “off-on” configuration, more convenient and efficientdetection, but the practical application environment, while moderate to detect theorganism, the fluorescence intensity of fluorescent probes are often subject to theexcitation light intensity, light leakage photobleaching, probe concentration of. Thus, asingle wavelength fluorescence measurement in practice often produce false sig nals, sothat the measurement result is often produce errors. To eliminate this singlewavelength measurements because of the false signals generated by the current is theuse of fluorescent probes and the analyte intensity of the fluorescence effect chang e atdifferent wavelengths, and then by calculating the fluorescence intensity ratio, andother environmental factors to eliminate false signals generated the impact that theratio of fluorescent probes probes. Therefore, this paper, based on the principle offluorescence resonance energy transfer (FRET) designed a fluorescein-coumarin BO3-fluorescence ratio probe; based on the principle of photo-induced electron transfer(PET) designed a rhodamine-naphthalene imide probe fluorescence ratio of Zn2+.Initially, we designed and synthesized a molecule containing both fluorescein andcoumarin parent structure, expect to contain both the advantages of both, use undernormal temperature conditions BO3-can catalyze the removal of acetate groups of theprinciple of aromatic compounds, structural changes to achieve a conjugated molecule,which occurred in the fluorescence resonance energy transfer (FRET) effect, which wesuccessfully synthesized based on a specific detection BO3-fluorescein-coumarinfluorescence ratio probe. During the synthesis of the probe, the first through theN,N-diethyl phenol oxidation of a ring to give a coumarin derivative, diazotization andthen reduction to give an intermediate compound1; the other hand, brominesubstituting phthalic anhydride with resorcinol to form a ring structure to give theparent fluorescein derivative, and then by Sonogashira reaction, the connectionterminal acetylenic bond to give the intermediate compound2; last two intermediatecompound obtained by the reaction of a final Sharpless the goal of the probe molecule.After the probe molecules by spectral detection and analysis confirmed that the probe was added to the BO3-solution, the probe molecule can be made off of theacetate group, the occurrence of FRET effect, thus the fluorescence maximum emissionwavelength red shift. Further fluorescein BO3-coumarin fluorescence probe has highselectivity and does not affect other ions, there is little to no fluorescence ratioreported BO3-probe, so by design FRET effect such a probe fluorescence ratio is stillvery meaningful, in addition we have come to the probe has a better detection limit andlinear detection range, has a market prospect. The results were1H NMR,13C NMR andMS characterization and structure has been confirmed.Currently naphthalimide based PET probe effects have been valued by the people,but the ratio of Zn2+fluorescent probes report also almost no reports on the design andsynthesis of a rhodamine-Naphthalimide Zn2+fluorescence ratio probe, the resultswere1H NMR,13C NMR and MS characterization and structure has been confirmed.Hoping to achieve selective recognition of Zn2+effects, although not particularly goodresults, but to some extent, providing a possible route for the synthesis of thi s type ofprobe molecules.