Spheryx, Inc., 330 E. 38th St. #48J, New York, NY 10016, USA.
Spheryx, Inc., 330 E. 38th St. #48J, New York, NY 10016, USA.
Water Res. 2017 Oct 1;122:431-439. doi: 10.1016/j.watres.2017.06.006. Epub 2017 Jun 7.
Determining the size distribution and composition of particles suspended in water can be challenging in heterogeneous multicomponent samples. Light scattering techniques can measure the distribution of particle sizes, but provide no basis for distinguishing different types of particles. Direct imaging techniques can categorize particles by shape, but offer few insights into their composition. Holographic characterization meets this need by directly measuring the size, refractive index, and three-dimensional position of individual particles in a suspension. The ability to measure an individual colloidal particle's refractive index is a unique capability of holographic characterization. Holographic characterization is fast enough, moreover, to build up population distribution data in real time, and to track time variations in the concentrations of different dispersed populations of particles. We demonstrate these capabilities using a model system consisting of polystyrene microbeads co-dispersed with bacteria in an oil-in-water emulsion. We also demonstrate how the holographic fingerprint of different contaminants can contribute to identifying their source.
确定悬浮在水中的颗粒的大小分布和组成在多相多组分样品中可能具有挑战性。光散射技术可以测量颗粒尺寸的分布，但无法区分不同类型的颗粒。直接成像技术可以通过形状对颗粒进行分类，但对其成分几乎没有深入了解。全息表征通过直接测量悬浮液中单个颗粒的大小、折射率和三维位置来满足这一需求。测量单个胶体颗粒折射率的能力是全息表征的独特功能。此外，全息表征足够快，可以实时建立群体分布数据，并跟踪不同分散颗粒群体浓度的时间变化。我们使用由聚苯乙烯微球与水中油乳液中的细菌共分散的模型系统来演示这些功能。我们还演示了不同污染物的全息指纹如何有助于识别其来源。
