Immobilization of DNA using self-assembly and interaction of DNA with other molecules as well as its

随着人类基因组计划（HGP）的顺利实施，人类基因组的工作草图提前绘制成功，人类在生命科学领域的认知又前进了一大步。然而在知道基因图谱之后，接下来的问题是面对大量的基因或基因片断序列如何研究其功能，研究重点便是要搞清楚基因变体的生物学功能及其对生命、健康和疾病的意义。各种重大疾病的易感基因以及这些基因之间的相互作用关系，将是研究的重中之重。因而对DNA与其他分子相互作用的基础研究变得越来越重要。另一方面，利用基因检测来进行基因诊断和基因治疗迫切需要研制开发各种适用于不同使用环境下的或快速灵敏或高密度高通量或方便廉价的基因传感器、基因芯片。 要构筑基因传感器、基因芯片（包括光学、电化学和压电传感...With the revolutionary developments of Human Genome Project, we are entering a new era of scientific discovery that holds great promise for understanding the complexities of the life. But genome sequencing is only the first step toward achieving an understanding of gene and the following problems we encounter are to make out expression and functions of the sequence-known gene and how they affect t...学位：理学博士院系专业：化学化工学院化学系_物理化学(含化学物理)学号：B19982501

基于通用MCU的智能SFP光模块设计

本文介绍一种兼容Sff-8472协议的智能SfP光模块的设计方案,提出了一种通用的光模块数字诊断监测(ddM)的设计思路,适用于不同型号MCu的ddM系统。使用MCu的flASH存储A2H地址的内容,采用内外部校准相结合的新校准方式,更灵活,更简便。通过实际测试,该方案的精度满足协议的要求

Surface Electrochemical Studies of Ferrocene and Its Interaction with DNA

在研究碳纳米管电极上二茂铁电化学性质的基础上,应用二茂铁修饰电极和DNA修饰电极研究了二茂铁与小牛胸腺DNA的相互作用。结果表明,修饰电极上的二茂铁都呈现一对明显的氧化还原峰,二茂铁修饰电极与DNA的作用表现为氧化还原峰电流减小,与溶液中的两者作用情况类似,而DNA修饰电极与二茂铁的作用则表现为氧化还原峰电流增大。扫描电镜结果也证实了两种修饰电极上的二茂铁与DNA间的作用。此外,还讨论了二茂铁与DNA间的作用模式。The interaction of ferrocene with calf thymus DNA has been investigated by using the ferrocene and/or DNA modified electrodes based on the electrochemical properties of ferroceneon on the carbon nanotube_modified electrode. The results show that an obvious redox peak for ferrocene is exhibited on the modified electrode. There exists a decrease for the redox peak currents on the electrode modified by ferrocene in the presence of DNA, which is similar to their interaction in solution. However, when the electrode modified by DNA is used as the working electrode, the redox peak current appears an increase compared with that by using the carbon nanotube_modified electrode. The interaction between ferrocene and DNA is also proved by SEM. In addition, the interaction mode of ferrocene with DNA is discussed.广东省教育厅自然科学基金(Z03020);; 广州市科委(2004J1-C0091)资助项

聚苯胺纳米点的氧化还原态与其库仑台阶效应

应用电化学恒电位法结合模板法制备聚苯胺纳米点阵列,导电原子力显微镜研究处于不同氧化还原态的聚苯胺纳米点的I～V特性,发现只有处于部分氧化态(导电态)的聚苯胺纳米点才出现库仑台阶效应,还原和全氧化态聚苯胺纳米点不显示库仑台阶.初步探讨了上述现象

Density Functional Theoretical Study on SERS Chemical Enhancement Mechanism of 4-Mercaptopyridine Adsorbed on Silver

基于密度泛函理论计算和拉曼光谱理论分析,我们研究了对巯基吡啶(4MPY)分子的拉曼光谱和其在银上的表面增强拉曼光谱(SERS),并进一步探讨了S; ERS与界面吸附结构、异构化、质子化和氢键作用以及低能激发态的关系。首先,我们对两种分子异构体的相对稳定性和拉曼光谱进行了理论分析。在此基础上,; 进而研究了该分子与不同银簇作用时的拉曼光谱,结果表明,4MPY以巯基硫与银簇作用形成强的Ag-; S键,导致拉曼光谱的线型不依赖于所选银簇的大小。接着我们考虑了吡啶氮端作用的两种情况。(1)当4MPY-银簇复合物同时以吡啶氮与水簇或水合质子簇; 形成氢键时,结果表明吡啶环的部分振动频率随氢键和质子化发生蓝移。(2)当考虑吡啶氮与银簇作用时,吡啶环三角畸变振动发生蓝移。上述情况不仅解释了实; 验观测的振动频率变化,而且表明了化学环境改变对相对拉曼强度的影响。最后,我们计算了当对巯基吡啶分子以单端或双端与银簇作用,在考虑激发光与低能激发; 态的能量匹配时,拉曼光谱强度与低能激发态的关系。计算结果表明,在双端吸附构型下,与吡啶氮成键的银簇受激发产生电荷转移态,不仅导致吡啶环v_(12; )、 v_1和v_(8a)振动的拉曼信号增强,而且选择性地增强吡啶环C-H面内对称弯曲振动v_(9a)的拉曼信号。Surface-enhanced Raman spectroscopy (SERS) is one of the most powerful techniques for obtaining fingerprint information on molecules adsorbed on coinage metal surfaces. Its detection sensitivity has reached the single-molecule level. On the basis of density functional theoretical (DFT) calculations and Raman scattering theory, we investigated the normal Raman spectra of two isomers and surface-enhanced Raman scattering (SERS) spectra of 4-mercaptopyridine (4MPY) adsorbed on silver. The results aided us in uncovering the relationships between normal Raman spectra and SERS spectra and adsorption configuration, tautomerization, protonation, and hydrogen bonding interactions as well as low-lying excited states. First, we compared the relative stability and normal Raman spectra of two isomers of 4MPY in the gas phase and aqueous solution with a solvent model similar to the solvation model of density (SMD). We then studied the Raman spectra of 4MPY interacting with silver clusters. Our results indicate that the Raman spectra were not dependent on the size of the silver clusters, owing to the formation of strong Ag-S bonds. We also considered two cases of N-end interaction in the 4MPY-Ag-5 complex. (1) For the hydrogen bond interaction between the nitrogen in 4MPY and water clusters or hydrated proton clusters, the theoretical results indicated that the vibrational frequencies of the pyridine ring increase. (2) For the interaction of the 4MPY-Ag-5 complex with a silver cluster Ag-4 through the lone-paired orbital in nitrogen of the pyridine ring, the theoretical results further revealed that the vibrational frequency shift is in good agreement with SERS peaks reported in the literature. Finally, our calculated results focused on the relationship between the Raman spectra and the charge transfer mechanism when the excitation photonic energy matches the transition energy of low-lying excited states in single-end and double-end adsorption configuration. Particularly for the case of the double-end adsorption configuration, the charge transfer states from the excitation from the silver cluster binding to the pyridine ring not only enhance the Raman signals of v(12), v(1), and v(8a) modes, but also selectively enhance the Raman signal of the v(9a) mode associated with the symmetric C-H in-plane bending vibration.国家自然科学基金（21273182,21533006,21373172）资助项

高序热解石墨与玻碳电极上DNA的氧化和吸附行为

在高序热解石墨（ＨＯＰＧ）电极上，采用微分脉冲伏安法（ＤＰＶ）和电化学原子力显微镜法（ＥＣＡＦＭ）探究小牛胸腺ＤＮＡ（ＣＴＤＮＡ）在电极表面的吸附．实验发现，控制电位下预极化对双链ＤＮＡ在ＨＯＰＧ电极上的吸附有很大的影响，而对单链ＤＮＡ影响不大．实验表明，在ＨＯＰＧ电极上ＥＣＡＦＭ是ＤＮＡ研究领域十分有用的技术，根据ＡＦＭ图象，结合文献上的ＤＮＡ吸附模型提出了ＣＴＤＮＡ在ＨＯＰＧ电极表面ＤＮＡ吸附的模型．本文还首次采用现场紫外可见反射光谱研究ＤＮＡ的电化学行为，发现对研究ＤＮＡ的吸附该技术具有比伏安法更高的灵敏

化学修饰阳极氧化铝模板法合成小尺寸聚苯胺纳米线

利用表面活性剂对阳极氧化铝(AAO)模板进行化学修饰,发展了模板合成法,从而得到更小尺寸的聚苯胺纳米管、线.在表面活性剂十八烷基脂肪酸(R18)修饰下,在14nm孔径的AAO模板中合成7nm的纳米线.对不同表面活性剂的比较后发现,通过改变修饰表面活性剂上烷基链长可以对所制备的聚合物纳米管、线的直径进行调控

自组装金团簇电极库仑台阶现象和电化学阻抗谱研究

采用示差脉冲伏安法研究了自组装单层保护金纳米团簇(C8AuMPC)在常温下二氯甲烷溶液中的量子化电容充电效应.研究结果表明,该团簇在-0.8~0.8V电位范围内有4对明显的量子化电容充电峰.同时采用电化学阻抗谱对C8AuMPC修饰金电极体系的界面结构进行了表征,研究结果表明,MPC自组装层存在两个界面,即金电极-MPC层界面和MPC层-溶液界面;这两个界面的界面电容在MPC的零电荷电位(ca.-0.2V)附近均基本保持不变,随着电位正移或负移到一定程度,界面电容发生变化.进一步利用双隧道结金属岛库仑阻塞效应理论讨论了已有报道中对MPC量子化电容充电的理论分析结果,并证明电化学阻抗谱也是研究MPC量子化电容充电效应的有效方法.另外,用示差脉冲伏安法及循环伏安法研究了电活性物种二茂铁对C8AuMPC量子化电容充电的影响,发现溶液中的电活性物种对MPC层-溶液界面的电子传递的贡献可以忽略,表明该界面的电子传递主要发生在纳米粒子之间

纳米硫化镉在对氨基苯硫酚自组装单层修饰金电极上的电化学合成

采用电流脉冲法在自组装了对氨基苯硫酚单层的金电极(PATP/Au)上电沉积硫化镉(CdS)纳米薄膜,运用扫描电子显微镜(SEM)和X射线衍射谱(XRD)对其形貌和结构进行了表征,发现得到的是垂直基底生长的CdS纳米棒有序阵列.研究电沉积中电流脉冲参数的影响时发现:随着电流脉冲宽度增大,CdS纳米棒的尺寸增大,有序性降低;脉冲幅度增大,则纳米棒尺寸增大,覆盖度也随之增大.因此通过调节脉冲宽度和脉冲幅度,可对所制备的CdS纳米薄膜的形貌和尺寸进行调控.运用循环伏安法和计时电位法对电沉积机理进行了探究.根据实验结果我们认为Au电极自组装PATP单分子层后,PATP分子中的-NH2与溶液中Cd2+相互作用,使沉积时的电子通过表面的PATP分子链进行传递.并进一步提出纳米CdS在PATP/Au电极上电化学合成的生长机理

多级树状纳米结构聚苯胺的电化学制备

建立一种无模板的恒电位电聚合方法,可在室温下制备对甲基苯磺酸(p-TSA)掺杂的多级树状纳米结构聚苯胺(PANI).根据电聚合曲线分析了PANI的聚合机理.扫描电镜(SEM)、透射电镜(TEM)观察表明制备的PANI具有均匀的多级树状纳米结构.紫外可见吸收光谱(UV-Vis)和红外光谱(FTIR)则显示所制备的PANI为掺杂态.该电沉积方法具有简便、易操作的特点,还可应用于其它纳米结构导电聚合物的可控制备