Metallic Surfaces and Particles in DNA Analysis

DNA 分析中的金属表面和颗粒

• 批准号: 6766896
• 负责人: Joseph R. LAKOWICZ
• 金额: $ 20.79万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-06-27 至 2006-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6766896
• 关键词: DNA; biomaterial interface interaction; biotechnology; fluorescence; fluorescence microscopy; fluorescence resonance energy transfer; heavy metals; microarray technology; molecular film; nucleic acid hybridization; nucleic acid quantitation /detection; nucleic acid structure; particle; polymerase chain reaction; rare earth element; silver; surface coating

DESCRIPTION (provided by applicant): We propose to evaluate and develop the use of metallic particles to modify fluorescence as used in DNA analysis. Fluorescence measurements are usually performed in optically homogeneously media, providing little opportunity to modify fundamental spectral properties. In contrast, recent experiments from this laboratory have shown that proximity of fluorophores to conducting metallic surfaces can increase radiative decay rates, increase quantum yields, decrease lifetimes and improve photostability. We expect these effects to substantially increase the number of photons which can be emitted by a single fluorophore. We will use silver particles and coated metallic surfaces to: 1. Examine the effects of metallic surfaces on the intrinsic emission of DNA, bases and nucleotides. The metallic particles will include silver island films, annealed films, colloids, clusters of colloids and coated metallic surfaces. 2. Examine the effects of these metallic particles on extrinsic probes commonly used to label DNA, and to explore the use of low quantum yield probes which become fluorescent near metallic surfaces. 3. Determine the effects of metallic surfaces on the rates and maximum distances for fluorescence resonance energy transfer (RET). We expect RET near metallic surfaces to extend to hundreds of A, as compared with the usual upper limit near 60 Angstroms. 4. Evaluate the use of lanthanides and transition metal-ligand complexes on DNA arrays containing metallic surfaces. These longer lived probes are highly photostable and may become useful on DNA arrays with the increased emission rate expected near metallic particles. 5. Apply the knowledge gained from Specific Aims1-4 for use on DNA arrays designed for rapid identification of antibiotic, resistant bacteria and environmental pathogens such as C. dipthariae and V. cholerae. Most experiments will be performed using metallic silver, but gold will be examined with longer wavelength DNA probes. Both intensity and lifetime measurements will be used to separate increases in the radiative rates from other effects of the sample on the fluorophore. Both one-photon and multi-photon excitation will be used. We expect this project to determine how metallic particle effects on fluorescence can be used for new approaches to DNA analysis.

描述（由申请人提供）： 我们建议评估和开发使用金属颗粒来修改用于DNA分析的荧光。荧光测量通常在光学均匀介质中进行，几乎没有机会修改基本光谱特性。相比之下，该实验室最近的实验表明，荧光团接近导电金属表面可以增加辐射衰减率，增加量子产率，减少寿命并提高光稳定性。我们预期这些效应将显著增加单个荧光团可以发射的光子数量。我们将使用银颗粒和涂层金属表面： 1.研究金属表面对DNA、碱基和核苷酸的固有发射的影响。金属颗粒将包括银岛膜、退火膜、胶体、胶体簇和涂覆的金属表面。 2.研究这些金属颗粒对通常用于标记DNA的外来探针的影响，并探索使用低量子产率探针，这些探针在金属表面附近发荧光。 3.确定金属表面对荧光共振能量转移（RET）速率和最大距离的影响。我们预计金属表面附近的RET将扩展到数百埃，而通常的上限接近60埃。 4.评估镧系元素和过渡金属配体配合物在含有金属表面的DNA阵列上的使用。这些寿命较长的探针是高度光稳定的，并可能成为有用的DNA阵列与金属颗粒附近的预期增加的发射速率。 5.将从Specific Aims1 - 4中获得的知识应用于设计用于快速鉴定抗生素、耐药细菌和环境病原体（如C.白喉和霍乱弧菌。大多数实验将使用金属银进行，但金将使用波长更长的DNA探针进行检查。强度和寿命测量将被用来分开的其他影响的样品上的荧光团的辐射率的增加。将使用单光子和多光子激发。我们希望这个项目能够确定金属颗粒对荧光的影响如何用于DNA分析的新方法。