The Application Research Of Fluorescent Probe On The Detection Of Small Molecular Pollutants

Recently,fluorescence detection method has become a hot spot.The detection of heavy metal ions content in the environmental water,atmosphere and soil by using the fluorescent probe has been widely used.The advantages of this method included rapid detection,simple operation and obvious signal.The thesis designed and synthesized two type fluorescent probe and they could respectively detect lead and ferric ions.The content was mainly described as follows:1.A new selective fluorescent chemosensor based on rhodamine 6G derivative?R1?has been designed and synthesized and the synthetic fluorescent probe R1 were characterized by means of infrared spectra,1H-NMR and13C-NMR spectra,high mass spectrometry and elemental analysis.The chemical synthesis method simple,the productive rate high and the experimental conditions mild.The product easy to be separated and the appropriate storage temperature for the compounds was about 0 4?.2.The probe R1 displayed highly selective and sensitive detecting for lead ion in aqueous solution.It belongs to the fluorescence enhancement type.Probe R1 was selective toward Pb²⁺ ion by a light yellow to pink change for the visual detection of Pb²⁺ion.The fluorescence recognition processes of Pb²⁺was based on a binding induced ring-opening from the spirolactam?nonfluorescent?to acyclic xanthenes?fluorescent?.Sensor R1 was excited with a 1:1 binding ratio and the linear response in the range of 1.0×10-8-1.0 ×10-5 mol L-1with the limit of detection of 2.7×10-9 mol L-1?S/N = 3?.3.Fe₃O₄ nanoparticles around 50 nm were prepared using modified chemicalco-precipitation,and corresponding thiolated function nanoparticles were also obtained via surface selenium dioxide and mercaptoacetic acid.The nanocomposite particle could be used as a fluorescent probe for detecting Fe3+.It belongs to the fluorescence quenching type.Particle surface of the mercapto complexed Fe3+ then reduced fluorescence intensity.The linear response in the range of 5.0×10-6 7.0×10-5mol L-1 with the limit of detection of 1.8×10-7 mol L-1?S/N = 3?.The synthesis method of mercapto Fe₃O₄ nanocomposite particle was simple,inexpensive and convenient.It also displayed highly selective and sensitive detecting for ferric ion.