CHARACTERIZATION AND QUANTIFICATION OF IMMOBILIZED DNA

在拟议的工作中，将探索在金表面上制备有序的寡核苷酸和多核苷酸薄膜的各种方案。重点将放在含有DNA分子的自组装单分子膜(SAM)的形成或将DNA分子附着到预制的烷硫醇自组装单分子膜上。这些薄膜将使用各种表面和分析技术进行量化和表征。五种技术将被用来提供关于非均相DNA传感器表面的详细描述：石英晶体微天平、原子力显微镜、扫描电化学显微镜、伏安法和电化学电感耦合等离子体-原子发射光谱分析。这些技术在DNA固定化、杂交插层和薄膜解吸方面的研究相互补充。我们打算将DNA固定化方案的设计、传感表面的表征以及由此产生的传感器的分析性能整合在一起。我们的最终目标是在分子水平上了解影响DNA传感器性能的某些重要因素(例如，固定化DNA的表面覆盖率、DNA分子取向、用于分析的探针和目标的最佳浓度，以及用于灵敏和选择性检测核酸的顺应性技术的开发)。

In the proposed work, various schemes for fabricating well-ordered oligonucleotide and polynucleotide films onto gold surfaces will be explored. Emphasis will be placed on the formation of self-assembled monolayers (SAMs) containing DNA molecules or attaching DNA molecules onto preformed SAMs of alkanethiols. These films will be quantified and characterized using a variety of surface and analytical techniques. Five techniques will be employed in an effort to provide a detailed description about the heterogeneous DNA sensor surface: quartz crystal microbalance, atomic force microscope, scanning electrochemical microscope, voltammetry, and electrochemical inductively coupled plasma (ICP)-atomic emission spectrometry ICP-mass spectrometry. These techniques complement one another in terms of studies of DNA immobilization, hybridization intercalation, and film desorption. We intend to integrate the design of the DNA immobilization scheme, the characterization of the sensing surface, and the analytical performance of the resulting sensor of the resulting sensor. Our ultimate objective is to understand certain important factors governing DNA sensor performance (e.g., surface coverage of immobilized DNA, DNA molecular orientation, optimal concentrations of the probe and target for an analysis, and the development of an amenable technique for sensitive and selective detection of nucleic acids) at molecular levels.