The Synthesis And Properties Of Fluorescent Probe Based Onthiophene Modified Rhodamine

Iron asthe basic trace element takes the highest percent in human body,playing an important role inhuman's growth and physiological functions.Iron mainly exists in human body by combining proteins.Iron deficiency leads to lower hemoglobin,causing iron deficiency anemia,fatigue,cold hands and feet,pale,insomnia diarrhea,etc.Over high content ofiron in body will cause iron poisoning and health damage.Aluminum,the highest content metal in the crust,is the main factor for acid soil pollution.Too much aluminum in body causes many diseases,such as encephalopathy,cartilage,anemia and Alzheimer's disease.Therefore,it is vital to developa kind of chemical probes that can identify Fe³⁺and Al³⁺ effectively.Fluorescence analysis method has been widely used in ion detection because of its advantages: simple operation,sensitive reaction and excellent selectivity.Rhodamine derivatives are the ideal fluorescent probe matrix for their special lactam structure and excellent fluorescence properties.In this paper,rhodamine B and rhodamine 6G were used as the probe matrix because of their specific lactam structure,and a series of rhodamine-type fluorescence sensors B2SY?BYJ?BYY?GYJ?GYY were synthesized and modificatedby thiophenecarboxylic acid and thiophene acetic acid.Their structures and properties were characterized and studied by using NMR Analysis,mass spectral analysis,UV and fluorescence analysis.This paper mainly includes the following three parts:First,introducing the concept,type and characteristics of fluorescent probes and the mechanism,development and achievements of Rhodamine chemical sensor.Second,using rhodamine B asmatrix,designing and synthesizing B2 SY,BYJ and BYY,according to the former study.Their structures and properties were studied by using nuclear magnetic,mass spectrometry,ultraviolet,fluorescence and other analysis:Compound B2 SY as an "naked-eye" probe has excellent selectivity for Fe³⁺ in ethanol-water?1: 4,v / v?solution.It complexed with Fe³⁺ in 1: 1,and the detect limitationis1.3?10-7 M,while the complexed stability constant is 2.95?104 M-1.B2 SY can also detect Fe³⁺ in the range of physiological pH and living cells effectively.Compounds BYJ and BYY can detect Fe³⁺ and Al³⁺ simultaneously without interfered with other metal ions.And BYJ-Fe³⁺ complex ratio is 1: 1,BYJ-Al³⁺,BYY-Fe³⁺,BYY-Al³⁺ complexes are all 1: 2.Third,compounds GYJ and GYY were synthesized by using rhodamine 6G as marix and modificatedby thiophene formic acid and thiophene acetic acid.And their optical properties were studied.Compound GYJ can react with Al³⁺,Fe³⁺ simultaneously,while accompanied by a color change from transparent to pink.GYJ-Fe³⁺ and GYJ-Al³⁺ are complexed at 1: 2,and the complexed constants are 3.91×108 M-2 and 5.26×108 M-2,respectively.Compound GYJ can penetrate into the cell membrane makes it a chemical sensor to detect Fe³⁺ and Al³⁺ in living cells effectively.Compound GYY can identify Fe³⁺ and Al³⁺ effectively,eliminating the interference of other metal ions,producing a color change?transparent to pink?.GYY and Fe³⁺ or Al³⁺ are complexed in the ratio of 1: 2,the complexed constants are 6.64×108 M-2 and 5.69×108 M-2,respectively.