Institute of Particle Technology (LFG), Friedrich-Alexander University Erlangen-Nürnberg (FAU) , Cauerstr. 4, 91058 Erlangen, Germany.
ACS Nano. 2014 Sep 23;8(9):8871-86. doi: 10.1021/nn503205k. Epub 2014 Aug 20.
The worldwide trend in nanoparticle technology toward increasing complexity must be directly linked to more advanced characterization methods of size, shape and related properties, applicable to many different particle systems in science and technology. Available techniques for nanoparticle characterization are predominantly focused on size characterization. However, simultaneous size and shape characterization is still an unresolved major challenge. We demonstrate that analytical ultracentrifugation with a multiwavelength detector is a powerful technique to address multidimensional nanoparticle analysis. Using a high performance optical setup and data acquisition software, information on size, shape anisotropy and optical properties were accessible in one single experiment with unmatched accuracy and resolution. A dynamic rotor speed gradient allowed us to investigate broad distributions on a short time scale and differentiate between gold nanorod species including the precise evaluation of aggregate formation. We report how to distinguish between different species of single-wall carbon nanotubes in just one experiment using the wavelength-dependent sedimentation coefficient distribution without the necessity of time-consuming purification methods. Furthermore, CdTe nanoparticles of different size and optical properties were investigated in a single experiment providing important information on structure-property relations. Thus, multidimensional information on size, density, shape and optical properties of nanoparticulate systems becomes accessible by means of analytical ultracentrifugation equipped with multiwavelength detection.
纳米颗粒技术的全球趋势是日益复杂化，这必须与更先进的尺寸、形状和相关特性的表征方法直接相关，这些方法适用于科学和技术中的许多不同的颗粒系统。现有的纳米颗粒表征技术主要集中在尺寸表征上。然而，同时进行尺寸和形状的表征仍然是一个未解决的主要挑战。我们证明，带有多波长检测器的分析超速离心法是一种强大的技术，可以解决多维纳米颗粒分析的问题。使用高性能的光学装置和数据采集软件，我们可以在一个单一的实验中获得有关大小、形状各向异性和光学性质的信息，具有无与伦比的准确性和分辨率。动态转子速度梯度使我们能够在短时间尺度上研究广泛的分布，并区分金纳米棒的不同物种，包括对聚集形成的精确评估。我们报告了如何仅通过使用依赖于波长的沉降系数分布，而无需耗时的纯化方法，在一个实验中区分不同类型的单壁碳纳米管。此外，还对不同尺寸和光学性质的 CdTe 纳米颗粒进行了研究，提供了有关结构-性质关系的重要信息。因此，通过配备多波长检测的分析超速离心法，可以获得关于颗粒系统的尺寸、密度、形状和光学性质的多维信息。
