The Study On Indoor Distribution System Project Management Optimization Program Of Jilin Unicom

As a novel two dimension carbon nanomaterials, graphene oxide （GO）composed of a single layer of sp²network of carbon atoms. It is well known that thearomatic compound can easily adsorbed on GO by π–π stacking. GO also have beenreported to interact strongly with nucleic acids through π–π stacking interactionsbetween the ring structures in the nucleic acids bases and the hexagonal cells of GO.Only single-stranded DNA can be stably adsorbed on GO; whereas double-strandedDNA （dsDNA） cannot because of efficient shielding of nucleobases within thenegatively charged dsDNA phosphate backbone. The adsorption behavior motivatesthe application for adsorbent, drug delivery and biosensors. Fe₃O₄magneticnanoparticles （MNPs） are attractive materials which are particularly useful forimaging and separation techniques due to their basic magnetic property. Excpet that,magnetic nanoparticle have been found its intrinsic catalytic activity, which can beused in bioanalysis as a peroxidase mimetic catalyst. When these two novelnanomaterials were combined, their advantage can be integrated to the benefit ofbiotechnology and biomedicine. In this paper, we focus on the application of GOand magnetic nanoparticles in a wide range of biological monitoring and analysis,summarized as follows:In the chapter1, we described the attractive properities of graphene and thedevelopment in methods for both graphene and magnetic nanoparticles. Then wefocused on their applications in bioanalysis and biomedicine. Finally, we providedinsights into utilization of their properities for developments of novel biotechnologyand the significance and contents of this dissertation.In the chapter2, we used gaphene oxide （GO） as a potential effective absorbentfor tetracycline antibiotics and remove them from aqueous solution. Tetracyclinestrongly deposited on the GO surface via π–π interaction and cation–π bonding. The adsorption isotherm fits Langmuir and Temkin models well, and the theoreticalmaximum of adsorption capacity calculated by Langmuir model is313mg g^-1,which is approximately in a close agreement with the measured data. The kinetics ofadsorption fits pseudo-second-order model perfectly, and it has a better rate constantof sorption （k）,0.065g mg^-1h^-1, than other adsorbents. The adsorption capacities oftetracycline on GO decreased with the increase in pH or Na⁺concentration. Theadsorption isotherms of oxytetracycline and doxycycline on GO were discussed andcompared.In the chapter3, a fluorometric method for quantity analysis of biothiols wasdeveloped using a GO-based “molecular beacon”-like probe, which consisted ofFITC labeled thymine-rich single-stranded DNA （ssDNA）, GO and Hg²⁺ions. Thelabeled ssDNA containing thymine-thymine （T-T） mismatches would hybridize toduplex in the presence of Hg²⁺, which can avoid its absorption to GO and retain thefluorescence of this GO-based probe. The fluorescence of the probe quenched afterthe addition of biothiols such as glutathione （GSH） and cysteine （Cys） owing to thiolgroups can selectively competitive ligation of Hg²⁺ions with T-T mismatches. In thepresent work, the GO-based probe was used for determination of GSH and Cys. Theproposed method was applied to the determination of GSH in human serum sampleswith satisfactory results.In the chapter4, we utilized the instinct peroxidase-like property of Fe₃O₄magnetic nanoparticles （MNPs） to establish a new fluorometric method fordetermination of hydrogen peroxide and glucose. In the presence of Fe₃O₄MNPs asperoxidase mimetic catalyst, H₂O₂was decomposed into radical that could quenchthe fluorescence of CdTe QDs more efficiently and rapidly. Then the oxidization ofglucose by glucose oxidase was coupled with the fluorescence quenching of CdTeQDs by H₂O₂producer with Fe₃O₄MNPs catalyst, which can be used to detectglucose. The proposed method was applied to the determination of glucose in humanserum samples with satisfactory results. In the chapter5, we reported a fluorescent magnetic multi-functional GO basednanomaterials used as nanocarriers for loading and delivery of water-solublearomatic anti-cancer drug, doxorubicine. We synthesized SiO₂microsphere encodedwith fluorescent CdTe quantum dots and Fe₃O₄magnetic nanoparticles andfunctionalized the SiO₂microsphere with amino groups. Then, the fluorescentmagnetic multi-functionalized SiO₂microspheres covalently bonded with GO via afacile amidation process between the carboxyl group on GO and the amino groupson SiO₂microspheres. The GO-based fluorescent magnetic hybrid was used asnanocarriers for loading and delivery of drug. The GO content in the hybrid acted asuniversal templates for loading drug; the magnetic nanoparticles were responsiblefor targeted delivery of the hybrid; and the quantum dots provided fluorescencesignal to show the trace of hybrid. We investigated the binding and release of DOXby this multi-functionalized GO-based hybrid in vitro. And the process of cellapoptosis was observed after cell phagocytosed the DOX loadedmulti-functionalized hybrid.