Fluorescence analysis has been widely used in biological analysis because of its high selectivity,high sensitivity,in situ detection,easy operation and so on.Fluorescent probe molecules with excellent properties are the key to the realization of highly sensitive fluorescence analysis.Oxygen anthracene fluorescent dyes such as rhodamine compounds are the candidate of small molecule fluorescent probes with their unique structure and excellent photoelectric properties.At present,most of the fluorescent probe molecules are fat-soluble molecules,in the practical application of the need to use organic solvent dissolved in order to achieve detection,there is poor biocompatibility and other issues.On the basis of the design and preparation of non-water-soluble fluorescent probe,we further explored the design,preparation and application of novel water-soluble fluorescent probe molecules in order to obtain high sensitivity water solubility with good biocompatibility Fluorescent molecules that provide candidate probe materials for on-line detection of biological samples.The main work and achievements of this paper are as follows:1.Six kinds of mercury ion fluorescent probes were designed and synthesized by using Schindamine B as the matrix and changing the groups of benzaldehyde,such as methyl,nitro,aldehyde,phenyl,halogen and so on.The complexes,detection range,detection limit and selectivity of the probe molecules and mercury ions were studied by fluorescence spectrophotometry.The effects of the substituent groups on the probe were investigated by means of the NMR spectra and the mass spectra.And the relationship between the probe structure and the response performance is obtained.The best-prepared probe L1{3’,6’-bis(diethylamino)-2-((4-methyl-benzylidene)amino)spiro[isoindole-1,9’-xanthene]-3-ketone}has good selectivity and anti-interference to mercury ions,and the complexation ratio of mercury ion is 1:1.The detection range is 0.05-140 μM and linear correlation coefficient is R2 = 0.9866.The limit of detection is 0.05 μM and the complexation constant is 3.24 × 103 M-1.Laser confocal fluorescence imaging showed that the probe L1 could penetrate the cell membrane successfully and be used in the detection of EC 109 cells.2.In order to improve the biocompatibility and reduce the use of organic solvents in the detection process on the basis of a series of non-water-soluble fluorescent probes synthesized in the previous section,we consider designing some water-soluble fluorescent probes to improve bioassay capability of rhodamine,we designed and synthesized three fluorescent probes to explore how to improve the water solubility of fluorescent molecular probes.The best ratio of water-soluble probe P2 to mercury ion was 1:1,the detection limit was 0.17 μM,and the complexing constant was 0.93 x 103 M-1.The detection range is 0.17-140 μM and the linear correlation coefficient is R2 = 0.9971.3.A novel copper ion probe L10 {3’,6’-bis(diethylamino)-2-(N-methylpyrrolidin-yl)spiro[isoindole-1,9’-xanthene]-3-ketone } was synthesized by the Schiff base reaction of rhodamine B hydrazide and pyrrole-2-formaldehyde.The probe could detect copper ions in ethanol solution and verified by mass spectrometry and NMR.The properties of the fluorescent probe were investigated by fluorescence spectroscopy,which proved that it could recognize copper ions well.The detection range was 0.17-180μM and the linear correlation coefficient was R2 = 0.9899.The detection limit of the probe is 0.17 pM,and the complexing constant is 1.18 × 103 M-1,which can serve as the naked eye detection. |