【作者】 乔春玉；

【导师】 周伟红；

【作者基本信息】 吉林大学 ， 分析化学， 2009， 博士

【摘要】 本论文应用荧光光谱和紫外-可见吸收光谱技术等对药物与生物大分子的相互作用进行了研究。共分为四章:第一章,分别对药物小分子与DNA和蛋白质相互作用的研究进行了综述。介绍了该研究领域所用的各种分析技术,以及药物与生物大分子相互作用的研究内容及现状。第二章,研究了中药有效组分蒽醌类化合物——大黄酚、大黄素甲醚和1,8 -二羟基蒽醌与DNA相互作用的光谱性质,并计算得到了不同温度下的结合常数等定量数据,探讨了温度和离子强度对结合反应的影响,并确定了这些化合物与DNA的主要结合模式。第三章,以EB为DNA的荧光探针研究了芦丁、金丝桃苷和槲皮苷与DNA的相互作用,探讨了荧光猝灭过程的性质,并计算得到了这些化合物与DNA-EB的结合常数。通过熔点、离子强度和粘度的影响等实验的研究,推测了芦丁、金丝桃苷和槲皮苷与DNA的主要结合方式。第四章,利用紫外-可见吸收光谱法和荧光猝灭技术分别研究了盐酸多西环素与人血清白蛋白和牛血清白蛋白的结合性质。由药物对血清白蛋白的荧光猝灭作用,计算得到了盐酸多西环素与血清白蛋白的结合常数,并根据热力学参数,确定了盐酸多西环素与HSA和BSA之间的主要结合力。实验还进一步研究了Ca2+,Mg2+,Zn2+,Fe3+和Cu2+存在时对结合性质的影响。更多还原

【Abstract】 The essential biological materials, such as nucleic acid and protein, have played vital roles in all kinds of biological phenomenan. They participate in many reactions. And the reactions and the function of nucleic acid and protein have high specificity. Medicines pass through several processes: absorption, distribution, metabolism and excretion from entering the organisms to leaving them. Nucleic acid and protein are the main targets of all drugs in organisms. The forms and binding sites of the interactions between the drugs and biomacromolecules influence the physiological, physical and chemical characters of biomacromolecules. Therefore, the researches on the functions between medicines and the nucleic acids or the proteins have the special value to design new medicines and study the pharmacology and toxicity of anticancer medicines. In this paper, the interactions of some drugs with DNA and serum albumin were studied by fluorescence and ultraviolet-visible absorption spectrometry.The structure and nature of DNA cannot be directly studied by fluorescence technique because the fluorescence of DNA is very weak, and the fluorescent probes can be brought in to solve this problem. Ethidium bromide is used as the earliest and broadest fluorescent probe. It can be used in the selecting of anticancer treatment medicine and the sensitive probe of binding mechanism between medicine and DNA. Chrysophanol, physcion and 1, 8-dihydroxy anthraquinone are the effective components in traditional herbal in China for treating various diseases. They possess antibacterial, laxative, and antitumor functions. In this work, the binding mechanism on the reaction of fish sperm deoxyribonucleic acid (DNA) with anthraquinones, such as chrysophanol, physcion and 1,8-dihydroxy anthraquinone, were investigated using ethidium bromide (EB) as fluorescence probe by fluorescence quenching technique and UV–vis spectrophotometry. The fluorescence intensities of DNA-EB were measured at different concentrations of anthraquinone compounds. According to the relationship of the fluorescence intensity and quenching reagent concentration, the binding constants of anthraquinones with DNA-EB complex at 25°C were figured out. The binding constants of chrysophanol, physcion and 1,8-dihydroxy anthraquinone with DNA-EB were 1.64×104,3.04×104,2.88×105 L·mol-1, respectively. In the experiment, the effects of the temperatures and ionic strength were further obtained. And the effects of DNA melting were also investigated, after three anthraquinones was added into the solution containing the DNA-EB. These studies suggest that the binding mode of chrysophanol, physcion and 1, 8-dihydroxy anthraquinone with DNA were evaluated to be groove binding.Ethidium bromide (EB) is a typical intercalative reagent of DNA. Its binding to DNA makes the fluorescence intensity of the system greatly enhanced. The interaction mechanisms of flavonoids, such as rutin, hyperoside and quercitrin, and DNA were studied using EB as fluorescence probes by fluorescence and ultraviolet-visible absorption spectrometry. Flavonoid is a secondary metabolite plant of widespread distribution. They widely exist in vegetables, fruits and medicinal plants. Their poisonous effect is small, and is one of the main active constituents in the medicinal plant. Here, the interactions of rutin, hyperoside and quercitrin with fish sperm deoxyribonucleic acid (DNA) by using EB as fluorescence probe were first reported. The character of fluorescence quenching process was investigated by spectrometric methods. The binding constants of flavonoids-double stranded DNA (dsDNA) or flavonoids-single stranded DNA (ssDNA) were obtained by the fluorescence quenching technique. Further, the effects of ionic strength and temperature on the fluorescence property of the system have also been investigated. The melting temperature (Tm) and viscosity of DNA was carried out to investigate binding mechanism of these flavonoids with DNA. The results of the assay indicate that the binding mode of rutin, hyperoside and quercitrin with DNA was evaluated to be intercalative binding. The binding constants of rutin, hyperoside and quercitrin with dsDNA (or ssDNA)-EB complex are 3.72×104 (or 7.65×103), 1.13×105 (or 5.73×104) and 5.59×104 (or 3. 63×104) L·mol?1, respectively.Doxycycline Hyclate is a semi-synthetic tetracycline antibiotic. It is frequently used to treat chronic prostatitis, sinusitis, syphilis, chlamydia, pelvic inflammatory disease, acne and rosacea. There are several advantages, such as relatively cheap, minor side-effects, and a slim risk of liver damage during prolonged use of the drug. Distribution and metabolism of many pharmaceutical molecules in the body are correlated with their affinities toward serum albumin. In this paper, the interactions of doxycycline with human serum albumin (HSA) and bovine serum albumin (BSA) were studied by fluorescence and ultraviolet-visible absorption spectrometry. The results showed that the fluorescence of serum albumins was strongly quenched by doxycycline. The quenching mechanism was static quenching procedure proved by the quenching rate constant (Kq). The main acting forces between doxycycline and serum albumins were hydrophobic force according to the thermodynamic parameters. The binding constants of doxycycline with human serum albumin and bovine serum albumin at different temperatures were obtained. The effects of metal ions, such as Ca2+, Mg2+, Zn2+, Fe3+ and Cu2+, on binding constants were also evaluated.更多还原