NIR-Capable stopped-flow spectrophotometer for inorganic nanomaterials

适用于无机纳米材料的近红外停流分光光度计

• 批准号: 374816-2009
• 负责人: Jones, Nathan
• 金额: $ 5.31万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments - Category 1 (<$150,000)
• 财政年份: 2008
• 资助国家: 加拿大
• 起止时间: 2008-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=412019
• 关键词: NIR; Capable; stopped; flow; spectrophotometer

When their physical dimensions are reduced to the nanometer scale, materials assume size-dependent properties that are remarkably different from those of the bulk substance (1 nanometer = 1 billionth of a meter). For example, nanoscale crystals of some materials can be made to emit light in the near infrared (NIR) region of the electromagnetic spectrum. This wavelength range is particularly useful for medical imaging and telecommunications applications, which require light to penetrate efficiently through biological tissue and along glass fibres. The wavelength of emission may be selected fairly precisely by making the crystals larger or smaller: larger crystals give longer emission wavelengths, while smaller crystals give shorter ones. The sizes of the crystals are in turn dependent on the synthetic protocols used to make them, and much trial and error is involved in the process of uncovering reliable and reproducible methods to give high quality, brightly emitting, nanocrystals of programmable size. In order to develop these methods more rationally, we propose to uncover the mechanisms by which the nanocrystals grow, and to use this knowledge to inform next-generation synthetic protocols. We will accomplish this using the requested NIR-capable stopped-flow spectrophotometer. This instrument rapidly and efficiently mixes the reactive molecular precursors to the nanocrystals, and then follows the formation and growth of these nanocrystals by monitoring changes in the colour of the reaction mixture in terms of both absorbed and emitted light. This allows us to determine the kinetics, or rate, of growth and, by modeling these data, to determine the mechanisms by which the crystals form and grow. We will also use the stopped-flow instrument as a tool for rapid discovery of synthetic protocols by semi-quantitative, iterative improvement methods. In these ways, we hope to be able to control with high precision the size, size distribution, and possibly also shape of important NIR-emitting nanomaterials with significant high-tech applications.

当它们的物理尺寸减小到纳米尺度时，材料呈现出与尺寸相关的性质，这些性质与散装物质的性质（1纳米=十亿分之一米）明显不同。例如，可以使某些材料的纳米级晶体发射电磁光谱的近红外（NIR）区域中的光。该波长范围对于医学成像和电信应用特别有用，其需要光有效地穿透生物组织并沿沿着玻璃纤维穿透。发射波长可以通过使晶体变大或变小来相当精确地选择：较大的晶体产生较长的发射波长，而较小的晶体产生较短的发射波长。晶体的尺寸又取决于用于制造它们的合成方案，并且在发现可靠和可重复的方法以提供高质量、明亮发射的可编程尺寸的纳米晶体的过程中涉及大量的试验和错误。为了更合理地开发这些方法，我们建议揭示纳米晶体生长的机制，并利用这些知识为下一代合成方案提供信息。我们将使用所要求的具有NIR功能的停流分光光度计来完成此操作。该仪器快速有效地将反应性分子前体与纳米晶体混合，然后通过监测反应混合物在吸收和发射光方面的颜色变化来跟踪这些纳米晶体的形成和生长。这使我们能够确定生长的动力学或速率，并通过对这些数据进行建模来确定晶体形成和生长的机制。我们还将使用停流仪器作为通过半定量、迭代改进方法快速发现合成方案的工具。通过这些方式，我们希望能够高精度地控制具有重要高科技应用的重要近红外发射纳米材料的尺寸，尺寸分布，以及可能的形状。