Synthesis Of Fluorescent Dye DTAF-MOR And Its Metal-enhanced Fluorescence Effect

Reactive fluorescent dyes can specifically conbine with biomolecules at the site of-OH?-SH and-NH2,of which they become very important fluorescent probes and mainly used in life-science,pharmaceutical chemistry,analytical chemistry andmany other filed.5-amino-fluorescein(5-AF)is one with reactive group,because of low quantum yield,it can't be practically applied.In this paper,we treated 5-AF as matrix and cyanuric chloride as a linker,by ading morphore group which was a nitrogen hetero,and synthesized a new reactive fluorescent dye 5-[(4-morpholine-6-chlorine-1,3,5-s-triazine)-amino]fluorescein(DTAF-MOR).This structure can not only increase the fluorescent quantum yield,and posses a newly reactive bonding site as well as a good fastness to textiles,but also get a stronger complexation ability for metal ions.Moreover,it can change the pH sensitive area and be more sensitive to the environment.Furthermore,metal-enhanced fluorescence(MEF)effect can increase the sensitivity of fluorescent dyes and their photostability.The interference of background spectra can also be decrease,which brodan their applications.So here we also studied MEF effect of silver particles,which laied a foundation for metal ions in preparing new reactive fluorescence amplifying sensors.The mainly contents and results are as follows:Firstly,based on the reactivity of cyanuric chloride at different temperature,we synthesized reactive fluorescent dye DTAF-MOR with four steps.And studied its fluorescent properties and analyzed its feasibility in becoming sensors.The results showed that the optical physics properties of DTAF-MOR were better than those of 5-AF,among which,the quantum yield increased from 0.017 to 0.294,at the same time,the Stokes Shift,fluorescent energy yield,oscillator strength and lifetime were raised to some extent.Moreover,DTAF-MOR was sensitive to concentration?solvent?pH value and metal cations,such as Mg2+?Ni2+?Mn2+?Cu2+?Zn2+?Fe2+?Co2+,and was most affected by Mg2+?in formating complex compound,and the comples ratio of DTAF-MOR to Mg2+ is 4:1.Secondly,we prepared spherical silver nanoparticles and silver rod particles with seed-mediated method.The influence of the mole ratio of the raw materials,temperature and pH value on the yield and uniformity of spherical silver nanoparticles were qualitatively investigated.The effects of the dosage of seed,ascorbic acid and cetyl trimethyl ammonium bromide on silver rod were also studied.Then,MEF effect on the two kinds of silver particles were detected.The results showed that more spherical silver nanoparticles brouhgt brighter fluorescent,no matter forfluorescein(FL),6-carboxyl fluorescein(6-FAM)or DTAF-MOR.Among them,6-FAM was the best because of more proper distance between dye molecule and silver particles.And DTAF-MOR was better,FL was the worst one.Only when the absorption resonance spectrum of silver rod colloid mostly overlaped with excitation or emission spectrum of DTAF-MOR,its MEF effect was better.