Synthesis And Performance Test Of A Two - Photon Fluorescence Probe Based On Spiro - Double Fluorene Structure

Spirobifluorene, which possesses good thermal stability, is a chemical compound whose structure is three dimensional space orthorhombic. The fluorescent probe that contains spirobifluorene has many merits, such as big molar absorption coefficient, high fluorescence quantum yield and two-photon absorption. Therefore, we can obtain fluorescent materials with relatively high fluorescence quantum yield by introducing appropriate fluorescent genes at the right position of 9,9’-spirobifluorene. The two-photon fluorescent probe not only serves a very important function in discovering the mysteries, improving clinical diagnosis and screening drugs, but also effectively avoids optical damage and photo bleaching which are the single-photo fluorescent probe’s defects. An excellent two-photo fluorescent probe should have a wide two-photon absorption cross-section, a good water-solubility and a high photo-stability, and it should respond the receptor sensitively. Because related reports are few, this paper combines these characteristics and synthetizes two unreported organic two-photo fluorescent probes with spirobifluorene structure. They have a fine two-photon absorption performance, selectivity and sensitivity.This paper does the following work:(1) We have designed a cheap and feasible route to synthetize spirobifluorene. We have got two compounds whose matrix is di-tert-butyl. One is “up-down” asymmetry type: SPF-DDA and SPF-SNC; the other is “left-right” asymmetry type: SPF-DAD andSPF-NCS.(2) We have studied the related performance upon the objected compounds SPF-DAD and SPF-DDA.1.Studies on the fluorescent performance of two-photon. SPF-DAD,s two-photon absorption cross-section is 726 GM, which proves that it has a good two-photon absorption performance. 2. Studies on the spectral properties and electrochemical properties of SPF-DAD which has been made into electrical luminescent devices to show that it can be used as luminescent materials and hole transport materials. 3.Tests on pH performance. The results show that it can be used as pH fluorescent probe within the scope of weak acidity and alkalescence. 4. We have studied SPF-NCS’s recognition upon six Amino acids,which are L- tryptophan, L-phenylalanine, L- glutamic acid, proline L-, L- aspartate and D- proline respectively. UV shows that Ultraviolet absorption has little decrease only at the peak. Besides,we have carried on the titration of Benzoyl isocyanate upon SPF-NC and tested FL’s variation over time after adding superfluous Benzoyl isocyanate and FL produced by adding different concentrations of Benzoyl isocyanate. The result shows that after adding superfluous Benzoyl isocyanate,Fluorescence intensity weakens with the passage of time,and finally disappears;After adding different concentrations of Benzoyl isocyanate,Fluorescence intensity weakens with the Benzoyl isocyanate concentration increasing.