Fluorescent Probes Based On Pyrene:Design,Synthesis And Application To The Detection Of Pollutants In Water

Fluorescent probes have been widely used in environmental monitoring,food safety and biosensors due to their rapid response,high selectivity and sensitivity,less sample consumption and operational simplicity.Pyrene and its derivatives are one type of particularly useful materials for the applications and designs of fluorescent probes.In recent years,they have received considerable attentions owing to their chemical stability,long fluorescence lifetime and high quantum yield.8-hydroxy pyrene-1,3,6-trisulfonate trisodium salt(HPTS)is a water-soluble pyrene with a ultrahigh quantum yield,large stokes shift and high extinction coefficient.However,there is a little with respect to the report of sensing application of HPTS.In this dissertation,several water soluble probes based on HPTS have been designed and synthysized.The optical properties of them and their applications to the detection of environmental pollutants in water are studied systematically.1.P-Nitroaniline(PNA)is one kind of highly toxic aromatic amine and becomes an environmental pollutant in recent years.The construction of a fluorescent sensor based on HPTS for the rapid and visual detection of PNA in aqueous media is reported.The fluorescence quenching of HPTS caused by the presence of PNA is through non-covalent interactions.The detection limit of this approach can be as low as 4.63 ?M and the linear detection range is between 0 and 120 pM by fluorescence measurements.The probe can be used not only for visualization of p-nitroaniline,but also enables the rapid detection of PNA for the real water samples.2.A water-soluble fluorescent probe,HPTS-1,was synthesized by one-step method,the nucleophilic nature of hydrogen sulfide was used to break the ether bond of the probe and release the fluorescent substance.Based on this off-on signal mode for the detection of hydrogen sulfide,we investigated the effects of different buffer solutions,temperature and pH on the detection of hydrogen sulfide.Through the experimental results,we found that the probe was simple preparation,water solublity,high sensitivity and selectivity.3.A novel fluorescent probe HPTS-DNP was designed and synthesized based on water-soluble pyrene derivatives for the detection of thiophenol in off-on signal mode in 100%aqueous medium.It has a very simple preparation,rapid reaction,visual inspection,excellent water solubility,excellent sensitivity and high selectivity.The detection limit is as low as 0.49 nM,and the probe actually detects the concentration of thiophenol as low as 1 nM.As far as we know,this is currently the minimum detection limit for fluorescence detection of thiophenol.4.The determination of thiophenol using HPTS-DNP in Houhai and tap water was studied,found that the probe can be used for qualitative and quantitative detection thiophenol in the real samples.In the Houhai system,the concentration of thiophenol in the range of 0.1 ?M to 50 ?M is linear with the relative fluorescence intensity I/I0.The correlation coefficient r is 0.999 and the detection limit is 1.54 nM.Meanwhile,the maximum strength of the I/I0 can be enhanced 2250 times.In the tap water system,the concentration of thiophenol in the range of 0.1 ?M to 50 ?M is linear with the I/I0.The correlation coefficient r is 0.998 and the detection limit is 4.04 nM.In this concentration range,The maximum increase of the I/I0 was 900 times.The probe was applied to Hela cells and 16 HBE cells for cell proliferation toxicity and cell fluorescence imaging.In Hela cells,50 ?M probe incubated in cells for 24 hours,have no fluorescence appears.However,in 16 HBE cells,the probe exhibits low toxicity and good membrane permeability.It can recognize thiophenol specifically in the cell.