Synthesis Of A Fluorescent Molecular Probe 4-bis(2-hydroxyethyl Amino)-ethylamino-N-n-butyl-1, 8-naphthalimides

4-bis(2-hydroxyethyl amino)-ethylamino-N-n-butyl-1,8-naphthalimides, a novel water soluble fluorescent molecular probes, was synthesized by using 4-bromo-1,8-naphthalic anhydride and n-butane amine as starting materials, based on photoinduced electron transfer(PET). The influence factors of processes were discussed and the optimum reaction conditions were obtained by experiments. For the first step, the yield can reach 83.6% under the optimum condition that 1 mol 4-bromo-1,8-naphthalic anhydride and 2.5 mol n-butane amine were reacted for 5h at 80℃. For the second step, the optimal reaction time and temperature were 5.5h and 125℃. Similarly, the optimal reaction time and temperature of the third and fourth step were 3.5h and 55℃, 10h and 100℃, separately.IR,1H NMR, MS were used to characterize the products. The optical properties of the product were determined and studied by ultraviolet-visible spectrum and fluorescent spectrum. The result indicated that the probes had stronger fluorescence in water solution of mercury ion. The excited and the emitted wavelength of the fluorescent molecular probe in standard solution are 425nm and 545nm, respectively. The lowest detective limit is 0.249×10-6mg·/L. On the whole, the fluorescent molecular probe NA1 is an easily-synthesized mercury ion probe with good stability, high sensitivity and selectivity, it can be successfully applied to the detection of mercury ion.