Synthesis Of Fluorescent Probe Based On Quinoline Derivatives And Their Application For Detecting Metal Ions

There has been paid much attention to metal pollutant in the environment for along time and it is significant for monitoring and separating metal pollutants in thefield of environment protection and biology. Therefore, fluorescent probe has a broadapplication prospect in the field of detecting metal ions due to its advantages ofsimple synthesis, rapid response, high sensitivity and good selectivity. In this thesis,we designed and synthesized a series of fluorescent probes and nano materials basedon the fluorophore of quinoline, and tested their fluorescence sensing properties andbiocompatibilities. All the compounds obtained were charaeterized by1H NMR and13C NMR.1. We successfully designed and synthesized a simple quinoline-basedfluorescent probe HQ for detecting Cu2+in near-aqueous media. The experimentalresults showed that HQ was a highly sensitive "off-on" fluorescence probe towardsCu2+. The fluorescent intensity of HQ enhanced linearly with the addition of Cu2+.The association constant of HQ with Cu2+was5.716×104mol-1by calculation fromthe1:1complexes and the detecting limit was calculated to be4.23×10-6mol/L.Simultaneously, the other common metal ions would not influence the detecting ofCu2+. Moreover, the cell fluorescence imaging experiment revealed the excellentbiocompatible ability of HQ and it could indeed visualize the changes of intracellularCu2+in living cells.2. A novel schiff based fluorescent probe was synthesized by combiningquinoline with pyridine moiety (Probe1). The experimental results showed thatProbe1was a highly sensitive "on-off" fluorescence probe towards Cu2+. Thefluorescent intensity of Probe1quenched with the addition of Cu2+. The associationconstant of Probe1with Cu2+was3.179×105mol-1by calculation from the1:1complexes and the detecting limit was calculated to be6.17×10-7mol/L.Simultaneously, the other common metal ions would not influenced the detecting ofCu2+. In addition, the cell fluorescence imaging experiment revealed that Probe1could be a valuable molecular sensor for studying biological processes involving Cu2+ within living cells.3. A novel schiff based fluorescent probe was synthesized by combiningquinoline with4-(Diethylamino) salicylaldehyde (Probe2). The experimental resultsshowed that Probe2was an excellent fluorescence probe towards Cu2+. Thefluorescent intensity of Probe2quenched with the addition of Cu2+. The associationconstant of Probe2with Cu2+was4.7735×108mol-1by calculation from the1:1complexes and the detecting limit was calculated to be6.6623×10-8mol/L.Simultaneously, Probe2dispalyed an excellent selectivity towards Cu2+amongcommon metal ions. Moreover, the cell fluorescence imaging experiment revealed thegood biocompatible ability of Probe2.4. A novel schiff based fluorescent probe was synthesized by combiningquinoline with phenothiazine (Probe3). The experimental results showed that Probe3was a highly sensitive "on-off" fluorescence sensor towards Hg2+. The fluorescentintensity of Probe3quenched with the addition of Hg2+in a linear relationship. Theassociation constant of Probe3with Hg2+was8.667×106mol-1by calculation fromthe1:1complexes and the detecting limit was calculated to be3.139×10-7mol/L.Simultaneously, the other common metal ions would not influence the detecting ofHg2+. In addition, the cell fluorescence imaging experiment also demonstrated thatProbe3could visualize the changes of intracellular Hg2+in living cells.5. Novel nanofibrous film with the probe for Cu2+was fabricated byelectrospinning. The fluorescent film displayed excellent sensitivities for Cu2+due tothe high surface area-to-volume ratio of the nanofibrous film structures, whichensured the fluorophore moieties were exposured to the determinands. Thefluorescence test revealed that the detecting limit of the nanofibrous film towardsCu2+could be micromolar level.