Synthesis Of Solid Substrate-Room Temperature Phosphorescence Labeling Reagents And Study On Their Applications In Analytical Chemistry

The using of SiO₂ nanoparticles,dendrimers,dissolved fullerene as phosphorescence labeling reagents were carried out and their application for the trace determination of bio-active compounds and environmental toxic ionics were investigated by solid substrate room temperature phosphorimetry(SS-RTP).This dissertation consists of four chapters.In chapter one,the research progress of SS-RTP and its influence factors were reviewed.Firstly,the effects of solid substrate,heavy ionic perturbation reagent, oxygen and humidity on the sensitivity of SS-RTP were introduced.Secondly, developing new solid substrate room temperature phosphorescence labeling reagents was put forward as a direct and efficient approach to improve the sensitivity of SS-RTP.Besides,the research progress of labeling reagents was reviewed.Finally,the objectives of this dissertation were brought forward.In chapter two,the synthesis and characterization of morin-labeled luminescent silica nanoparticles combined with palladium that used as the phosphorescence probe for DNA detection was carried out.Luminescent silica nanoparticles doped with Morin(Morin-SiO₂) were prepared by sol-gel method by using Na₂SiO₃ as the precursor and Morin as organic dye.Transmission electron microscope(TEM) demonstrated the sizes of SiO₂·nH₂O nanoparticle and Morin·SiO₂ nanoparticle were both 50 nm.Morin·SiO₂ nanoparticle modified with HS-CH₂COOH is water soluble. In HMTA(hexamethylenetetramine)-HCl buffer solution,Pd²⁺ could coordinate with Morin in Morin·SiO₂ nanoparticle to form complex Pd²⁺-Morin·SiO₂,which could emit phosphorescence on polyamide membrane.And DNA could cause a sharp enhancement of the room temperature phosphorescence(RTP) intensity of complex Pd²⁺-Morin·SiO₂.Thus a new method of solid substrate room temperature phosphorescence enhancing for the determination of DNA was established based on the luminescent Morin·SiO₂ nanoparticles-Pd system.Theâ–³Ip was directly proportional to the content of DNA in the range of 4.00-1000.0 fg spot^-1 and the detection limit was 0.61 fg spot^-1.Disturbances of common ions,such as Mg²⁺,K⁺, and Ca²⁺,were small,and there was no disturbance in the presence of protein and RNA.This method has been applied to the determination of DNA in nectar successfully.In chapter three,the determination of glucose by affinity adsorption solid substrate-room temperature phosphorimetry based on concanavalin agglutinin labeled with fluorescein using 1.5-generation dendrimers as sensitizer was discussed.In the presence of the heavy atom perturber Pb(Ac)₂,fluorescein(HFin) can emit strong and stable room temperature phosphorescence on the surface of a nitrocellulose membrane (NCM).It can be spiked with the 1.5-generation polyamidoamine dendrimers(D-1.5) to emit stronger RTP.It was found that a quantitative specific affinity adsorption(AA) reaction between concanavalin agglutinin(Con A) labeled with D-1.5-HFin and N-acetylglucosamine(G) could be carried out on the surface of NCM.The product of the reaction(D-1.5-HFin-Con A-G) could emit strong and stable RTP,and theâ–³Ip was proportional to the content of G.The linear range of the sandwich method was 0.040-60 pg spot^-1.Compared with the direct method(linear range:0.40-40 pg spot^-1) the sensitivity was obviously improved and the linear range was wider.This method has been successfully applied to the determination of G in human plasma,as well as to the supervision and forecast of human diseases.In chapter four,the determination of trace lead using p-nitro-phenyl-fluorone-multi-wall carbon nanotubes-Tween-80 micellae compound and diagnosis about human diseases by SS-RTP was discussed.The structures of multi-wall carbon nanotubes(MWNTs) were modified by H₂SO₄-HNO₃ and H₂SO₄-H₂O₂,respectively. The corresponding products were water-soluble MWNTs-A and MWNTs-B. According to the experiment,it was found that MWNTs-B could emit stable solid substrate-room temperature phosphorescence on the surface of paper with Ag⁺ as perturber.Under the conditions of 70℃and 15min,MWNTs-B can react with Tween-80 and p-nitro-phenyl-fluorone(R) to form R-MWNTs-B-Tween-80 micellae compound,which could emit RTP of R and MWNTs-B on the surface of paper, respectively.Pb²⁺ can cause sharp enhancements of the RTP of R and MWNTs-B, respectively.â–³I_p is directly proportional to the content of Pb²⁺.Thus,a new solid substrate-room temperature phosphorimetry for the determination of trace Pb²⁺ has been established based on R-MWNTs-B-Tween-80 micellae compound containing double luminescent molecule.This method is of high sensitivity,good selectivity,high precision and accuracy.It could be applied to determine trace Pb²⁺ in serum samples at wavelength of 453.7/623.0 nm(R) or 475.9/645.0 nm(MWNTs-B) with satisfactory results,showing that SS-RTP has flexibility and utility value.Simultaneously,this method can be used to diagnose human diseases.The reaction mechanism for the determination of trace Pb²⁺ by SS-RTP based on R-MWNTs-B-Tween-80 micellae compound containing double luminescent molecules was also discussed.