NONLINEAR OPTICAL ABSORPTION OF DNA-FUNCTIONALIZED CARBON NANOTUBES

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 单壁碳纳米管是一种分子线，具有有趣的结构、电化学和光学性质。聚合物功能化和生物材料功能化的单壁碳纳米管的近红外光学吸收特性在光学纳米生物传感器中引起了特别的关注。 脱氧核糖核酸(DNA)在生物体中发挥着重要的生理和病理作用。单壁碳纳米管独特的结构性质使其作为大分子酶和DNA的载体非常有用。DNA功能化的单壁碳纳米管的光学性质对过氧化氢、葡萄糖、蛋白质、氧气、氨和抗坏血酸等许多化学和生物材料都很敏感。这为我们开发光学生物医学传感应用提供了有用的途径。 过氧化氢是许多酶催化化学反应的主要产物之一。过氧化氢在生命系统中的过度积累与衰老和严重疾病有关。研究发现，DNA功能化碳纳米管在近红外波段的线性光学吸收特性与过氧化氢的浓度密切相关。这一计划集中在双链DNA功能化碳纳米管的非线性光学吸收特性上。我们将使用纳秒脉冲近红外激光系统和开孔Z-SAN技术来表征双链DNA功能化碳纳米管分散体在不同过氧化氢浓度下的非线性光吸收系数，以确定非线性光吸收系数与过氧化氢浓度的关系。这项研究可以从分散体扩展到本学年的双链DNA功能化碳纳米管薄膜。这一结果将增强双链DNA功能化碳纳米管在光学生物传感中的应用潜力。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Single-walled carbon nanotubes are molecular wires that exhibit interesting structural, electrochemical, and optical properties. The near-infrared optical absorption properties of polymer- and biomaterial-functionalized single-walled carbon nanotubes have attracted particular attention for optical nanobiosensors. Deoxyribonucleic acids (DNAs) play important physiological and pathological roles in living organisms. The unique structural properties of single-walled carbon nanotubes make them extremely useful as a carrier of macromolecular enzymes and DNAs. Optical properties of DNA-functionalized single-walled carbon nanotubes are sensitive to many chemical and biological materials such as hydrogen peroxide, glucose, protein, oxygen, ammonia, and ascorbic acid. This provides us with useful approaches to develop optical biomedical sensing applications. Hydrogen peroxide is one of the main products for many enzyme-catalyzed chemical reactions. The over accumulation of hydrogen peroxide in living systems is related to aging and severe diseases. It has been found that the linear optical absorption properties of DNAfunctionalized carbon nanotubes in the near-infrared range significantly depend on the concentration of hydrogen peroxide. This proposed program concentrates on nonlinear optical absorption properties of double-stranded DNA-functionalized carbon nanotubes. We will use a nanosecond pulsed near-infrared laser system and employ the open aperture Z-san technique to characterize nonlinear optical absorption coefficient of the dispersions of double-stranded DNA-functionalized carbon nanotubes under different concentrations of hydrogen peroxide to determine the relation between the nonlinear optical absorption coefficient and the concentration of hydrogen peroxide. This research can be extended from the dispersions to the thin films of double-stranded DNA-functionalized carbon nanotubes during the academic year. The results will reinforce the potential of double-stranded DNA-functionalized carbon nanotubes for use in optical biosensing.