Synthesis And Fluorescence Sensing Properties Of Phosphorus-Containing Organic Molecules

Organic small-molecule fluorescent probes are of interest because of their controllable synthesis,stable luminescence,high selectivity and sensitivity,high signal-to-noise ratio,and suitable for real-time analysis of living systems.Their photochemical properties are more stable than other types of probes,thus contributes to stronger fluorescence emission and high spatial resolution.In addition,fluorescence analysis is widely used because of simple operation,high selectivity and sensitivity,high spatial and temporal resolution,low limit of detection,and real-time detection.Therefore,the development of organic small-molecule fluorescent probes is of great importance in research field such as ion and biological small molecule detection.In this thesis,four phosphorus-containing organic small-molecule fluorescent probes,such as PPP,PPPO,DAC-P and TPE-P,were designed and synthesized for the sensitive detection of Sudan red Ⅰ（SudanⅠ）,bilirubin（BR）and vitamin B12(VB₁₂)respectively.The main research includes the following three parts:Part 1:Design and synthesis of an AIE phosphole organic fluorescent probe for the efficient detection of SudanⅠSudan redⅠ（SudanⅠ）is a red chemical colouring agents,which has mutagenic and carcinogenic to humans.Therefore,it is of great significance for sensitive detection of SudanⅠin food.In this study,two AIE phosphole small-molecule fluorescent probes（PPP and PPPO）for the efficient detection of SudanⅠwere designed and synthesized.Both phosphole compounds have strong fluorescence emission in the solid state and are stable in air.The results suggested that PPP and PPPO could be used for well-quantified concentration of SudanⅠ,and in the concentration range from 0.01 to 80μM（PPP）and0.3 to 250μM（PPPO）,the limit of detection were 6.25 nM（PPP）and 16.10 nM（PPPO）.These two fluorescent probes were also successfully used for the detection of SudanⅠin chili powder and tomato sauce.The related experimental data intimated that the quenching mechanism are inner filter effect（IFE）.This study is of great significance to the analytical chemistry of food and the organic phosphine chemistry.Part 2:Design and synthesis of an organic fluorescent probe for the efficient detection of bilirubin in human serumBilirubin（BR）is an important biomarker that can be used for clinically diagnosing the infant jaundice,which is one of the leading causes of death in newborns within the first day.Therefore,accurate detection of bilirubin in human serum is of great significance for newborn.In this study,an organic fluorescent probe DAC-P for the efficient detection of BR was designed and synthesized.DAC-P is constructed from the fluorophore coumarin and diphenylphosphine,the excitation and emission wavelengths of the probe are range from 350 to 550 nm.DAC-P with good luminescent properties and could be used for well-quantified concentration of BR,and in the concentration range from 0.5 to20μM,the limit of detection was 0.23μM.Furthermore,DAC-P was also successfully used for the detection of BR in human serum.The related experimental data intimated that the quenching mechanism was inner filter effect（IFE）.Part 3:Design and synthesis of an AIE organic fluorescent probe for the efficient detection of VB₁₂Deficiency or excessive intake of vitamin B12(VB₁₂)may result in a variety of related symptoms occurring,such as pernicious anemia and neurotoxicity.Therefore,accurate detection of VB₁₂ is very important for human health.In this study,an AIE organic small-molecule fluorescent probe TPE-P for the efficient detection of VB₁₂ was designed and synthesized.The probe TPE-P is constructed from the typical AIE molecule tetraphenylene and diphenylphosphine group.TPE-P is an organic luminescent material with good properties due to its strong fluorescence emission and stable in air.The results suggested that TPE-P could be used for well-quantified concentration of VB₁₂,and in the concentration range from 0.7 to 40μM,the limit of detection was 0.14μM.Fluorescent probe TPE-P was also successfully used for the detection of VB₁₂ in vitamin pills and drinks.The related experimental data intimated that the quenching mechanism was inner filter effect（IFE）.The constructed fluorescence sensing platform has potential application prospect in the real-time detection of VB₁₂ content.