Nanotechnology group of Malvern Panalytical Ltd., Grovewood Road, Malvern, WR14 1XZ, United Kingdom.
Sci Rep. 2020 Mar 13;10(1):4628. doi: 10.1038/s41598-020-61624-9.
With the industrialisation of nanoparticle manufacture, the pervasive incursion of nanoparticles into the environment, the need to characterise nano-scale pharmaceuticals and living systems in replicated in vivo conditions, the continuing development of new theories to describe the electro-kinetic behaviour of nano-particles in representative ionic strengths and numerous other applications, there is an urgent requirement to provide simple and effective experimental tools to validate these models and explore new systems. Micro-electrophoresis implemented with a diffusion barrier, which isolates the dispersed phase from the electrode surface, is demonstrated as enabling such measurements for the first time, preventing the catastrophic outgassing, precipitation and sample degradation observed when the dispersed phase is in close proximity to the electrode surface. Using a measurement of a few minute's duration in a standard laboratory light scattering instrument we reproduce the theoretically predicted phenomena of asymptotic, non-zero electrophoretic mobility with increasing ionic strength, the cationic Hofmeister series dependency, charge inversion and a continuously decreasing variation in mobility with pH as molarity increases. Standard operating procedures are developed and included to encourage further work.
随着纳米颗粒制造的工业化，纳米颗粒普遍侵入环境，需要在复制的体内条件下对纳米级药物和生命系统进行特性描述，不断发展新的理论来描述纳米颗粒在代表性离子强度下的电动行为，以及许多其他应用，因此迫切需要提供简单有效的实验工具来验证这些模型并探索新系统。扩散屏障微电泳的实现，将分散相从电极表面隔离，首次证明了这种方法的可行性，防止了当分散相接近电极表面时观察到的灾难性放气、沉淀和样品降解。我们使用标准实验室光散射仪器进行了几分钟的测量，重现了理论预测的随着离子强度的增加，电泳迁移率渐近、非零、阳离子哈夫迈斯特序列依赖性、电荷反转以及随着摩尔浓度增加，迁移率不断减小的现象。制定并包含了标准操作程序，以鼓励进一步的工作。
