The Synthesis And Applications Of A Amino Porphyrin Fluorescent Probe

Fluorescence analytical method has been rapidly developed for its high selectivity, easy to operate, small sample quantity, and other advantages. It has a higher sensitivity, which is about 2-3 orders of magnitude higher than spectrophotometry. Porphyrins are a class of macrocyclic compounds with rigid conjugate structure, it can easily emit strong fluorescence under irradiation. Porphyrin can chelated with most metal and non-metallic ions in the Periodic Table, and can be used for detections of varieties of metal ions for the research works of biochemical reaction and medical science.In this paper, the main task is to design and synthesize new types of Porphyrin probes, which have the excellent performances of easy to detect, high sensitivity, selectivity, and stability. Study the properties of fluorescent probes and their applications in the detection of heavy metal ions and H2O2 in water. Furthermore, to propose a new thinking of detection of pH and heavy metals using such fluorescent dye based fluorescence sensor. The details including three aspects are as follows:(1) A fluorescent dye,5,10,15,20-tetra(4-aminophenyl)-porphyrin (TAPP) with good stability, high sensitivity was synthesized by simple steps. The fluorescence properties of TAPP, and the effects of pH and surfactant on the fluorescence intensity were investigated. Results showed that it can be used for selectively sensing Ni(Ⅱ) and Co(Ⅱ) through complexation-induced fluorescence quenching. Additionally, the TAPP probe showed linear response toward Ni(Ⅱ) and Co(Ⅱ) in the concentration range of 2.0×10-7-1.0×10-5 mol/L. The prepared sensing system presented satisfactory sensitivity, and the detection limits could be as low as 4.0×10-8 mol/L for Ni(Ⅱ) and 2.0×10-8 mol/L for Co(Ⅱ). The developed method was successfully employed for preliminary application in natural water and domestic sewage.(2) The fluorescence probe of TAPP was used to determine the content of H2O2 in envrionment. In the concentration range of 2.0×10-6-1.0×10-4%, the fluorescence intensity of TAPP changed as linear function of H2O2 content. The prepared sensing system presented satisfactory sensitivity, and the detection limit could be as low as 6.0×10-7% for H2O2. The developed method was successfully employed for preliminary application in natural water and rain water. (3) The author tried to prepare new pH or heavy metal fluorescence sensors based on such fluorescence indicator of TAPP. Although the results are not satisfactory, the synthetic products, and sensors is still worth studying after improvement, and will be applied to the determination of pH and heavy metal ions.