基于碳纳米复合材料手性识别电活性小分子电化学传感器研究
发布时间：2018-08-22 07:55
【摘要】：手性是自然界的基本属性,手性化合物是生物体的基本组成成分。不同构型的手性化合物在医药科学、生命科学、食品科学、材料科学及环境等方面发挥着独特的作用,从而手性化合物对映体纯度和含量的测定成为当前化学的研究热点。因此发展低成本、检测快速的手性识别技术成为新的研究发展要求。电化学传感器因具有操作简便、检测快速、响应灵敏以及低成本、污染小等优点而作为一类新的测试手段应用于手性识别研究。碳纳米材料因具有大的比表面积、良好的化学稳定性及优良的电化学性质,被广泛用于合成纳米复合材料构建电化学传感界面,为电化学传感器应用于手性识别开拓了新的发展前景。本文主要通过合成新型碳纳米复合材料,并将其应用于构建手性传感表面,实现对电活性手性小分子实时在线、快速灵敏的手性识别检测。主要研究内容分为以下三部分：1.研究了新型多孔纳米复合材料对色氨酸对映体的手性识别。通过循环伏安技术在多壁碳纳米管(MWCNTs)修饰的玻碳电极上电聚合L-半胱氨酸(L-Cys),形成具有手性识别能力的多孔纳米复合材料(PLC/MWCNTs),并采用扫描电子显微镜(SEM)、循环伏安技术(CV)和电化学交流阻抗技术(EIS)对该材料进行表征。利用循环伏安技术研究该多孔纳米复合材料对色氨酸(Trp)对映体的手性识别作用。实验结果表明：该纳米复合材料与D-Trp的作用更强,从而实现了对色氨酸对映异构体的手性识别。2.研究了巯基化-β-环糊精/纳米金/石墨烯构建的手性表面对多巴对映异构体的手性识别作用。利用氨基化离子液体(IL-NH2)还原氧化石墨烯制备离子液体还原的氧化石墨烯(IL-rGO),并将其滴涂于玻碳电极表面,然后在其表面电沉积纳米金(dpAu),最后通过金-硫键作用在纳米金上自组装巯基化-β-环糊精(β-CD-SH),从而构建了具有手性识别能力的电化学传感界面。采用差分脉冲伏安法(DPV)研究多巴(DOPA)对映异构体在该手性表面上的电信号响应,发现D-DOPA的电流响应信号明显大于L-DOPA,由此说明：该手性表面与D-DOPA的作用强于L-DOPA。3.采用循环伏安技术和方波伏安技术对比研究了多壁碳纳米管、傒四甲酸(PTCA)和L-半胱氨酸形成的复合材料对多巴对映体的手性识别。利用π-π堆积作用制备傒四甲酸功能化的多壁碳纳米管,将其通过EDC/NHS与 L-半胱氨酸共价键合形成纳米复合材料(MWCNTs-PTCA-Cys),并利用循环伏安技术和扫描电子显微镜对该材料进行表征。然后将该复合材料修饰于玻碳电极上,利用循环伏安法(CV)和方波伏安法(SWV)对比研究其对多巴对映体的手性识别。实验结果表明：该复合材料与D-DOPA的作用时,电流响应更大,采用方波伏安法比循环伏安法达到了更好的识别效果。
[Abstract]:Chirality is the basic attribute of nature and chiral compounds are the basic components of organism. Chiral compounds of different configurations play a unique role in medicine science, life science, food science, material science and environment, so the determination of enantiomeric purity and content of chiral compounds has become a hot spot in current chemistry. Therefore, the development of low-cost, rapid detection of chiral recognition technology has become a new research and development requirements. Electrochemical sensors have been used as a new testing method for chiral recognition due to their advantages of simple operation, rapid detection, sensitive response, low cost and low pollution. Because of its large specific surface area, good chemical stability and excellent electrochemical properties, carbon nanocomposites are widely used in the synthesis of nanocomposites to construct electrochemical sensing interfaces. It opens up a new prospect for the application of electrochemical sensors in chiral recognition. In this paper, a new type of carbon nanocomposites was synthesized and applied to construct chiral sensing surface to realize real-time on-line detection of electroactive chiral small molecules and rapid and sensitive chiral recognition detection. The main research content is divided into the following three parts: 1. Chiral recognition of tryptophan enantiomers by new porous nanocomposites was studied. A porous nanocomposite (PLC/MWCNTs) with chiral recognition was prepared by electropolymerization of L-cysteine (L-Cys) on a multiwalled carbon nanotube (MWCNTs) modified glassy carbon electrode by cyclic voltammetry. A scanning electron microscope (SEM),) cyclic voltammetry technique was used. The material was characterized by (CV) and electrochemical impedance spectroscopy (EIS). The chiral recognition of tryptophan (Trp) enantiomers by the porous nanocomposites was investigated by cyclic voltammetry. The experimental results show that the nanocomposite has stronger interaction with D-Trp, thus realizing chiral recognition of tryptophan enantiomers. The chiral recognition of dopa enantiomers on the chiral surface of mercapto- 尾 -cyclodextrin / nano-gold / graphene was studied. Aminated ionic liquids (IL-NH2) were used to deoxidize graphene oxide to prepare graphene oxide (IL-rGO) reduced by ionic liquids, which were dripped on the surface of glassy carbon electrode. Then electrodeposition of nano-gold (dpAu), on its surface was carried out. Finally, the self-assembly of 尾 -CD-SH on nano-gold was carried out by gold-sulfur bond, and the electrochemical sensing interface with chiral recognition ability was constructed. Differential pulse voltammetry (DPV) was used to study the electrical response of the enantiomers of dopa (DOPA) on the chiral surface. It was found that the current response signal of D-DOPA was obviously larger than that of L-DOPA, which indicated that the interaction between the chiral surface and D-DOPA was stronger than that on L-DOPA. 3. Cyclic voltammetry and square wave voltammetry were used to investigate the chiral recognition of Dopa enantiomers in composites composed of multiwalled carbon nanotubes (MWNTs), tetracarboxylic acid (PTCA) and L-cysteine (L-cysteine). The functionalized multiwalled carbon nanotubes of tetracarboxylic acid were prepared by 蟺-蟺 stacking, and covalently bonded by EDC/NHS and L-cysteine to form nanocomposites (MWCNTs-PTCA-Cys). The materials were characterized by cyclic voltammetry and scanning electron microscopy. Then the composite was modified on glassy carbon electrode and the chiral recognition of dopa enantiomers was studied by cyclic voltammetry (CV) and square wave voltammetry (SWV). The experimental results show that the current response of the composite is greater than that of D-DOPA, and the square wave voltammetry is more effective than cyclic voltammetry.
【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB33;O657.1
本文编号：2196479
[Abstract]:Chirality is the basic attribute of nature and chiral compounds are the basic components of organism. Chiral compounds of different configurations play a unique role in medicine science, life science, food science, material science and environment, so the determination of enantiomeric purity and content of chiral compounds has become a hot spot in current chemistry. Therefore, the development of low-cost, rapid detection of chiral recognition technology has become a new research and development requirements. Electrochemical sensors have been used as a new testing method for chiral recognition due to their advantages of simple operation, rapid detection, sensitive response, low cost and low pollution. Because of its large specific surface area, good chemical stability and excellent electrochemical properties, carbon nanocomposites are widely used in the synthesis of nanocomposites to construct electrochemical sensing interfaces. It opens up a new prospect for the application of electrochemical sensors in chiral recognition. In this paper, a new type of carbon nanocomposites was synthesized and applied to construct chiral sensing surface to realize real-time on-line detection of electroactive chiral small molecules and rapid and sensitive chiral recognition detection. The main research content is divided into the following three parts: 1. Chiral recognition of tryptophan enantiomers by new porous nanocomposites was studied. A porous nanocomposite (PLC/MWCNTs) with chiral recognition was prepared by electropolymerization of L-cysteine (L-Cys) on a multiwalled carbon nanotube (MWCNTs) modified glassy carbon electrode by cyclic voltammetry. A scanning electron microscope (SEM),) cyclic voltammetry technique was used. The material was characterized by (CV) and electrochemical impedance spectroscopy (EIS). The chiral recognition of tryptophan (Trp) enantiomers by the porous nanocomposites was investigated by cyclic voltammetry. The experimental results show that the nanocomposite has stronger interaction with D-Trp, thus realizing chiral recognition of tryptophan enantiomers. The chiral recognition of dopa enantiomers on the chiral surface of mercapto- 尾 -cyclodextrin / nano-gold / graphene was studied. Aminated ionic liquids (IL-NH2) were used to deoxidize graphene oxide to prepare graphene oxide (IL-rGO) reduced by ionic liquids, which were dripped on the surface of glassy carbon electrode. Then electrodeposition of nano-gold (dpAu), on its surface was carried out. Finally, the self-assembly of 尾 -CD-SH on nano-gold was carried out by gold-sulfur bond, and the electrochemical sensing interface with chiral recognition ability was constructed. Differential pulse voltammetry (DPV) was used to study the electrical response of the enantiomers of dopa (DOPA) on the chiral surface. It was found that the current response signal of D-DOPA was obviously larger than that of L-DOPA, which indicated that the interaction between the chiral surface and D-DOPA was stronger than that on L-DOPA. 3. Cyclic voltammetry and square wave voltammetry were used to investigate the chiral recognition of Dopa enantiomers in composites composed of multiwalled carbon nanotubes (MWNTs), tetracarboxylic acid (PTCA) and L-cysteine (L-cysteine). The functionalized multiwalled carbon nanotubes of tetracarboxylic acid were prepared by 蟺-蟺 stacking, and covalently bonded by EDC/NHS and L-cysteine to form nanocomposites (MWCNTs-PTCA-Cys). The materials were characterized by cyclic voltammetry and scanning electron microscopy. Then the composite was modified on glassy carbon electrode and the chiral recognition of dopa enantiomers was studied by cyclic voltammetry (CV) and square wave voltammetry (SWV). The experimental results show that the current response of the composite is greater than that of D-DOPA, and the square wave voltammetry is more effective than cyclic voltammetry.
【学位授予单位】：西南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB33;O657.1
【参考文献】
相关期刊论文 前4条
1 石士考;纳米材料的特性及其应用[J];大学化学;2001年02期
2 李元宰;白采善;金京玉;;高效液相色谱法拆分α-氨基酸的邻苯二甲酰衍生物对映体[J];分析化学;2006年10期
3 翁文;韩景立;陈友遵;黄晓佳;;手性传感器研究进展[J];化学进展;2007年11期
4 ;Recognition behavior of chiral nanocomposites toward biomolecules and its application in electrochemical immunoassay[J];Science China(Chemistry);2010年06期
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