氧化石墨烯与石墨烯量子点在化学发光中的应用研究

发布时间：2018-11-24 14:22

【摘要】：化学发光是一种灵敏度高,线性范围宽,无背景干扰的分析方法,广泛应用于临床,医学,食品和环境分析等领域。氧化石墨烯(GO)和石墨烯量子点(GQDs)作为新型的碳材料,除了有与其他量子点可比的光学性能,还有毒性小,成本低,生态友好等优点。将GO和GQDs用于化学发光,不仅提高了化学发光的灵敏度,而且拓宽了碳材料的研究领域。在本论文中,我们将GO和GQDs结合流动注射进样技术应用于不同体系的化学发光中,研究结果如下:1.采用Hummers法合成GO并进行一系列表征,发现表征结果与文献报道相一致。将GO用于化学发光,发现在碱性条件下GO对鲁米诺(luminol)有明显的增敏作用从而建立GO-luminol体系。通过紫外吸收光谱、荧光光谱、化学发光光谱和其他化学实验对GO-luminol体系的发光机理进行探究,推测GO可能作为催化剂、氧化剂或者是孤对电子的受体诱导luminol产生化学发光。向GO-luminol体系中加入葛根素发现葛根素对体系的化学发光强度有明显的抑制作用,将该体系用于葛根素含量的测定。最优条件下,葛根素浓度的对数值与相对化学发光强度在0.01 6.00μM之间有线性关系,检出限为2.83 nM。对浓度为0.40μM的葛根素溶液平行测定11次,相对标准偏差为1.94%。将该方法用于中药葛根和尿样中葛根素含量的测定,回收率分别在98.0 102.0%和97.0 101.5%之间。2.以葡萄糖为原料高温裂解合成GQDs,对比不同时间对GQDs荧光强度的影响,发现加热90 s时的荧光量子产率比其他时间都高。将相对荧光量子产率较大的GQDs用于化学发光,发现在酸性条件下GQDs明显增敏KMnO4-NaHSO3微弱体系的化学发光,从而建立KMnO4-NaHSO3-GQDs新体系。在该体系中,培氟沙星的加入明显增强化学发光强度,建立了简单测定培氟沙星的方法。最优条件下,培氟沙星的浓度在0.04 8.00μM范围内与相对化学发光强度呈现良好的线性关系,检出限为0.01μM。将此方法用于培氟沙星片剂中培氟沙星含量的测定,回收率在97.5 101.8%之间。3.继续将GQDs用于化学发光发现在酸性条件下GQDs明显增强Ce(IV)-NaHSO3微弱体系的化学发光,从而构建Ce(IV)-NaHSO3-GQDs新体系。向该体系中加入酪氨酸,发现酪氨酸明显抑制体系的化学发光强度,建立了化学发光法测定酪氨酸。最优条件下,酪氨酸的浓度在0.02 8.00μM范围内与相对化学发光强度呈现良好的线性关系,检出限为4.1 nM。
[Abstract]:Chemiluminescence is an analytical method with high sensitivity, wide linear range and no background interference. It is widely used in clinical, medical, food and environmental analysis. As new carbon materials, graphene oxide (GO) and graphene quantum dot (GQDs) have the advantages of low toxicity, low cost and ecological friendliness, in addition to their optical properties comparable to those of other quantum dots. The application of GO and GQDs to chemiluminescence not only improves the sensitivity of chemiluminescence, but also broadens the research field of carbon materials. In this thesis, GO and GQDs combined with flow injection technique were applied to chemiluminescence of different systems. The results are as follows: 1. GO was synthesized by Hummers method and a series of characterizations were carried out. It was found that the results of characterization were consistent with those reported in the literature. When GO was used to chemiluminescence, it was found that GO could enhance the sensitivity of Luminol (luminol) in alkaline condition and establish the GO-luminol system. The luminescence mechanism of GO-luminol system was investigated by ultraviolet absorption spectrum, fluorescence spectrum, chemiluminescence spectroscopy and other chemical experiments. It was speculated that GO might be used as catalyst, oxidant or acceptor of solitary electron to induce chemiluminescence of luminol. The addition of puerarin to GO-luminol system showed that puerarin had obvious inhibitory effect on the chemiluminescence intensity of the system, and the system was applied to the determination of puerarin content. Under the optimal conditions, the logarithm of puerarin concentration has a linear relationship with the relative chemiluminescence intensity of 0. 01 ~ 6. 00 渭 M, and the detection limit is 2. 83 nM.. The relative standard deviation was 1.94 for the puerarin solution with a concentration of 0.40 渭 M for 11 times. The method was applied to the determination of puerarin in Pueraria and urine samples. The recoveries of puerarin were between 98.0 and 102.0% and 97.0 ~ 101.5%, respectively. Compared with the effect of different time on the fluorescence intensity of GQDs, synthesized by pyrolysis of glucose as raw material, it was found that the fluorescence quantum yield of GQDs heated for 90 s was higher than that of other time. GQDs with high relative fluorescence quantum yield was applied to chemiluminescence. It was found that GQDs could sensitize the chemiluminescence of weak KMnO4-NaHSO3 system obviously under acidic conditions, and thus a new KMnO4-NaHSO3-GQDs system was established. In this system, the addition of pefloxacin significantly enhanced the chemiluminescence intensity, and a simple method for the determination of pefloxacin was established. Under the optimal conditions, the concentration of pefloxacin in the range of 0.04 渭 M and 8.00 渭 M showed a good linear relationship with the relative chemiluminescence intensity, and the detection limit was 0.01 渭 M. The method has been applied to the determination of pefloxacin in pefloxacin tablets. The recoveries of pefloxacin in pefloxacin tablets ranged from 97.5 to 101.8%. The application of GQDs to chemiluminescence showed that GQDs enhanced the chemiluminescence of weak Ce (IV) NaHSO3 system obviously under acidic conditions, and thus constructed a new Ce (IV) NaHSO3-GQDs system. Tyrosine was added to the system and the chemiluminescence intensity of the system was obviously inhibited by tyrosine. A chemiluminescence method was established for the determination of tyrosine. Under the optimum conditions, the concentration of tyrosine in the range of 0.02 渭 M was linear with the relative chemiluminescence intensity, and the detection limit was 4.1 nM..
【学位授予单位】：山西师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O657.3;O613.71

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