Synthesis And Properties Of Fluorescent Fluorescence Probes

Design and synthesis of fluorescence chemsensors to achieve selective recognition of certain chemicals is one of the main content of supramolecular chemistry.Chemsensors can selectively identify target substances at the molecular level.It has high selectivity,high sensitivity,convenient detection of advantages.And it can be widely used in biomedical detection,nanomaterial science and environmental science and other related fields.In recent years,with the important understanding of anions in various fields,it has become a research hotspot to choose the form of certain anions.Among many anions,fluoride is a negative ion with strong electronegativity and the smallest radius.It plays an important role in every aspect of daily life.It is a necessary trace element,and the lack of fluoride in the human body could lead to dental caries and osteoporosis and other diseases,but excessive intake of fluoride will destroy the collagen,reduce the activity of the thyroid gland.In cytology and biology,sodium fluoride affects the transmission of cell signals,and high concentrations of fluoride lead to apoptosis in mammalian cells.More and more attention has been paid to fluorine ion fluorescent chemical sensors with high accuracy and sensitivity.In this paper,a series of organic functional small molecules with naphthalic anhydride,perylene and nitrobenzoxadiazole as fluorescent chromophores were synthesized.Their selective recognition ability for F-was studied by means of simple fluorescence color change and so on.The specific content is divided into the following three parts:The first part is a brief introduction to the role and harm of fluorine ions in life,and then introduces the concept and principle of fluorescent molecules and some anionic fluorescent probes.This paper also include the research status of fluoride chemosensors in recent years.Finally,these studies were analyzed,binding conditions and work basis,research ideas was put forward.In the second part,we design and synthesize organic fluorescent molecules based on naphthalene anhydride as chromophore for fluoride sensing.To improve the solubility and biocompatibility of the chemosensor,morpholine and imidazole fragment was introduced into the molecule.The structure of target molecule is indentified by infrared,H1NMR,C13NMR and MS.Through the forming hydrogen bond between amino group of sensor and F-,the sensing result could be oberseved by naked-eyes.The fluorescence titration showed that there was a good linear between the concentration of the chemosensor and F-,and the detection limit was calclulated was 1.7 × 10-7M.In the third part,the chemosensor for fluoride based on perylene and nitrobenz-oxadiazole as chromogenic groups was designed and synthesized.The structure of this chemosensor was indentified by infrared,H1NMR,C13NMR and MS,and their spectral properties were determined by color change and fluorescence emission spectroscop.The results showed that the two fluorescent molecules had good selectivity and higher sensitivity to fluorine ions.The fluorescence sensor B with perylene as chromophore group contains four Si-O bonds,which makes it more sensitive to fluorine ion detection,and the detection line reaches 3.5×10-8M.The fluorescence sensor C has good water solubility and biocompatibility,which lays the foundation for fluorine ion recognition in vivo.The detection limit of fluorine ion in PBS solution(containing 60%ethanol)is 1.7 × 10-6 M.