Construction And Application Of Hemi-cyanine Dye Optical Molecular Probes For Ozone,Acidity And Monosaccharide Compounds

BackgroundsOptical molecular probe is an optical analytical device with molecular size,which can produce photophysical processes such as transfer of electrons,charges or energy after specific binding with the substance to be measured,so as to realize the labeling or fluorescence microscopic analysis of poisons in organisms and the environment.The appearance of optical molecular probe provides a new application way for molecular recognition research in analytical chemistry.Because of its important use in environment,medicine and health,it has become one of the hot topics of international frontier research.Semi-cyanine dyes have the advantages of unique conjugated skeleton,designable structure,adjustable absorption and emission wavelength,etc.As the parent,the optical molecular probes made of them have been widely used in environmental monitoring and medical hygiene.Ozone（O₃）,as a typical substance in active oxygen,is a double-edged sword for human beings.The change of p H value in water phase and cells not only indicates the change of acid-base balance,but also relates to the occurrence and development of various diseases.As one of the three nutrients that sustain life,sugar plays an important role in human body.Therefore,it is of great significance to design and synthesize optical molecular probes for detecting O₃ molecules,water phase and intracellular p H values and monosaccharides.ObjectivesFour kinds of optical molecular probes with sensitivity and specificity were designed to visually detect O₃ molecules,p H values in water phase/cells and monosaccharides,which provided a fast and convenient detection method for the determination of O₃,p H values and monosaccharides in environment and biological media.Methods1 Design and synthesis the optical molecular probe Hemi-cyanine-butyltriene（HCB）which can be used to detect O₃ molecules,the optical molecular probe 1(Hemi-cyanine 1（HC₁）/Hydroxycyanine 2（Hemicyanine 2,HC₂）which can be used to detect p H values in water phase/cells,and Hemi-cyanine-Phenylboric acid（HPBA）which can be used to detect monosaccharide compounds.The structures of these four probes were characterized by NMR hydrogen spectrum,NMR carbon spectrum and mass spectrometry.2 Ultraviolet-visible absorption spectrum and fluorescence spectrum were used to investigate the spectral changes of HCB and O₃ molecules,HC_1/HC₂ and p H value,and HPBA and monosaccharides before and after combining.According to the change of spectrum,the optical properties of each probe molecule,such as the best binding conditions,selectivity and competitiveness,were explored to identify the corresponding target species.At the same time,according to the change of spectrum,combined with mass spectrometry and nuclear magnetic characterization,the reaction mechanism of each optical molecular probe to identify the target species was speculated.3 According to the color changes of HCB,HC₁/HC₂and HPBA when they interacted respectively with O₃ molecule,p H value and monosaccharide compounds,probe molecules were used for naked-eye detection of each target species.According to the changes of fluorescence intensity of HCB,HC₁/HC₂ and HPBA before and after binding with the corresponding target species in cell media,the application of probe molecules in the identification of target species in cell media was investigated by fluorescence confocal imaging technology.ResultsThe results of NMR hydrogen spectrum,NMR carbon spectrum and mass spectrometry showed that the probe molecules HCB,HC₁/HC₂ and HPBA had been successfully prepared.And could be used for sensitive detection of corresponding target species.1.The results of spectral detection showed that HCB showed high specificity for O₃recognition,and showed a good linear relationship in a wide range of 0-8.20×10^-5 mol/L,with the lowest detection limit of 2.15×10^-7 mol/L.At the same time,according to the changes of spectrum and fluorescence intensity in the recognition process,the visual detection of O₃ molecules in the environment and cell media could be realized.2.The color of the solution of p-hydroxyhemicyanine dyes HC₁ and HC₂ changed regularly with the change of the acidity of the solution,which can indicate the acidity of environmental water samples and cell media.3.The probe molecule HPBA showed a good spectral response to monosaccharides,with the lowest detection limits of 0.70×10^-3 mol/L for D-fructose,D-sorbitol,D-galactose and D-glucose respectively.2.50×10^-3 mol/L;2.20×10^-3 mol/L and 2.80×10^-3 mol/L.The method realized the detection of monosaccharide compounds in fruit samples,and provided a new idea for the evaluation of monosaccharide compounds in fruit samples.ConclusionsIn this paper,four optical molecular probes HCB,HC₁,HC₂ and HPBA were designed and synthesized.The results of ~1H NMR,¹³C NMR and MASS spectrometry showed that the four optical molecular probes were successfully prepared.The results of spectral response showed that all four optical molecular probes could present sensitive responses to target species.They were applied to the detection of corresponding target species in the environment and individual organisms,and compared with the traditional detection methods,they present the detection results of material number.