Staymates M E, Fletcher R, Verkouteren M, Staymates J L, Gillen G
The National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
Rev Sci Instrum. 2015 Dec;86(12):125114. doi: 10.1063/1.4938486.
We have developed a method to produce discrete microparticles from compounds dissolved in nonpolar or polar solvents using drop-on-demand inkjet printer technology. A piezoelectric inkjet printhead located atop a drying tube produces precise droplets containing defined quantities of analyte. Droplets solidify into microparticles with known composition and size as they traverse down the drying tube. Because this is a drop-on-demand printing process, a known number of droplets are produced providing quantitative particle delivery to a variety of substrates. Particular emphasis is placed on the development and characterization of the drying tube in this work. The drying tube was modeled using computational fluid dynamics and experimentally evaluated using laser-based flow visualization techniques. A notable design feature of the drying tube is the ability to push heated air through the tube rather than the need to pull air from the exit. This provides the ability to place a known number of well-defined particles onto almost any substrate of interest, rather than having to collect particles onto a filter first and then transfer them to another surface. Several types of particles have been produced by this system, examples of which are pure particles of cyclotrimethylenetrinitramine ranging from 10 μm to 30 μm in diameter, and ammonium nitrate particles of 40 μm diameter. The final particle size is directly related to the solute concentration of the printing solution and the size of the initial jetted droplet.
我们已经开发出一种方法，利用按需滴液喷墨打印机技术，从溶解于非极性或极性溶剂中的化合物制备离散的微粒。位于干燥管顶部的压电喷墨打印头产生含有特定量分析物的精确液滴。当液滴沿干燥管向下移动时，会固化成具有已知成分和尺寸的微粒。由于这是一个按需滴液打印过程，会产生已知数量的液滴，从而实现向各种基材定量输送颗粒。这项工作特别强调干燥管的开发和表征。使用计算流体动力学对干燥管进行建模，并使用基于激光的流动可视化技术进行实验评估。干燥管的一个显著设计特点是能够将加热的空气推过管子，而不是从出口处抽吸空气。这使得能够将已知数量的明确界定的颗粒放置在几乎任何感兴趣的基材上，而不必先将颗粒收集到过滤器上，然后再转移到另一个表面。该系统已经制备出几种类型的颗粒，例如直径在10μm至30μm之间的环三亚甲基三硝胺纯颗粒，以及直径为40μm的硝酸铵颗粒。最终颗粒尺寸与打印溶液的溶质浓度和初始喷射液滴的尺寸直接相关。
