Studying The Interaction Between Core-shell Quantum Dots And Alkaloid, Fluoroquinolones, And Metal Complexes, DNA By Resonance Rayleigh Scattering, Absorption And Fluorescence Spectra And Its Analytical Application

Core-shell quantum dots (QDs) are the new powerful tool for nanobiophotonics as a kind of novel fluorescent label. And comparing with narrow excitation, broad emission and narrow Stokes shift of traditional organic dyes, they possess tunable fluorescence emission, high photostability and attractive spectrum with almost symmetrical narrow emission and broad excitation; and they are scores of times as bright as the organic dyes at least. Due to such optical properties, in these years more and more important results have been achieved in bio-imaging and assay such as cell labeling, biomolecular detection and immunoassay. Although the strategies of synthesizing shell/core QDs are more popular and employed widely in biomedical diagnosis, it is still of importance to synthesize inexpensive QDs with high quality for application in biology. This thesis mainly focuses on the design, synthesis, optical properties, surface chemistry, bioactivity and biological application of QDs.The main results are as the following:1. Study on fluorescence spectrometry and UV-vis absorption spectra of interactions of core-shell CdTe/CdS QDs with Jatrorrhizine Hydrochlorid and Palmatine chloride and its DeterminationThe core-shell CdTe/CdS quantum dots (QDs) was synthesized using mercaptoacetic acid (TGA) as stabilizer. A novel method for determination of Jatrorrhizine Hydrochloride(JH) and Palmatine Chloride(PC) has been developed based on quenching of the fluorescence of CdTe/CdS QDs in excitation wavelength for340nm. The paper utilized fluorescence spectrometry and ultraviolet-visible (UV-vis) absorption spectra to study the interaction between CdTe/CdS QDs and Jatrorrhizine Hydrochloride(JH)/Palmatine Chloride(PC). With the optimum reaction conditions which was found to be at pH=7.4with tris-HCl buffer solution, the quenched fluorescence intensity of CdTe/CdS QDs was linearly proportional with correlation coefficient r=0.999/r=0.997, and the detection limits were in the range of11.04～1×104mg/L/25～1×104ng/mL and the detection limit for jatrorrhizine hydrochloride (3σ) was3.3mg/L、7.7ng/mL. Jatrorrhizine Hydrochloride(JH)/Palmatine Chloride(PC) will be quickly、simplely and conveniently、quantitatively detemination with this new method.2. Study on fluorescence spectrometry and UV-vis absorption spectra of interactions of core-shell CdTe/CdS QDs with Lomefloxacin Hydrochloride and its DeterminationThe core-shell CdTe/CdS quantum dots (QDs) was synthesized using Glutathione, GSH as stabilizer. A novel method for determination of Lomefloxacin Hydrochloride, LMFH has been developed based on quenching of the fluorescence of CdTe/CdS QDs in excitation wavelength for340nm. The paper utilized fluorescence spectrometry and ultraviolet-visible (UV-vis) absorption spectra to study the interaction between CdTe/CdS QDs and palmatine chloride. With the optimum reaction conditions which was found to be at pH7.6with tris-HCl buffer solution, the quenched fluorescence intensity of CdTe/CdS QDs was linearly proportional with correlation coefficient r=0.997, and the detection limits were in the range of27～2×104ng/mL and the detection limit for palmatine chloride (3σ) was8.2ng/mL. Lomefloxacin Hydrochloride will be quickly, simplely, conveniently and quantitatively detemination with this new method.3. Study on the system of GSH-CdTe/CdS、Cu(Ⅱ)-Lomefloxacin Hydrochloride and DNA by UV-vis, fluorescence and Rayleigh scattering spectrumWe used a low temperature water phase reaction to synthesize Glutathione ligand, GSH, for use in the preparation CdTe/CdS quantum dots (QDs). Fluorescence of GSH-CdTe/CdS QDs can be effectively quenched by binding of the complexes formed between Lomefloxacin Hydrochloride and metal ions Cu(Ⅱ) on their surfaces, enabling the electrostatic attraction process with the QDs and LMFH-Cu2+. Subsequent addition of hsDNA restored FL intensity to the QDs as LMFH-Cu2+dissociated from the surface and embedded into the hsDNA double helix structure, thus preventing the electrostatic attraction process with the QDs and LMFH-Cu2+. Reversible control of FL was realized for fluoroquinolones drugs through induced FL quenching and subsequent hsDNA-induced FL restoration for GSH-CdTe/CdS QDs. The reaction of GSH-CdTe/CdS QDs-LMFH-Cu2+-hsDNA is discussed on the basis of FL, resonance Rayleigh scattering and ultraviolet-visible absorption spectra and the spectroscopic method developed was used to investigate the interaction between anthraquinone anticancer drugs and DNA.