Asymmetrical flow FFF (AsFlFFF) is a member of field-flow fractionation (FFF) and can provide the separation of particles with size from nano to microscale based on their hydrodynamic diameters with smaller particles being eluted earlier than larger ones. For spheres, if the AsFlFFF conditions are well optimized, the FFF theory allows prediction of the elution time for a given diameter. Herein, we aim to use the AsFlFFF channel to compare the elution behavior of the gold nanoparticles with three different morphologies and give a comprehensive depiction for the mechanism of their separation in AsFlFFF. Furthermore, the particles size obtained from AsFlFFF was compared with that obtained from other techniques such as transmission electron microscopy (TEM), and dynamic light scattering. In this study, gold nanospheres (GNS), gold nanotriangles (GNT), and gold nanorods (GNR) were synthesized. TEM data stated that the mean particle diameter and the edge length of GNS and GNT were 51 and 35 nm, respectively, and the length of GNR was 47 nm. Although, the diameter of GNS is close to the length of GNR, the elution time of GNS (4.45 min) was much longer than that of the GNR (3.70 min) at the same AsFlFFF conditions. Also, the elution time of GNT was longer than that of GNR, even though it has smaller size than GNR. This might be attributed to GNR reaching an equilibrium position that is farther away from the accumulation wall of the channel than GNS, resulting in earlier elution than GNS. The GNT particles are rather similar in shape to spheres, and may behave more closely to the spheres than GNR. It seem that AsFlFFF could be an analytical technique for particle size analysis and separation of nanoparticles of different shapes.

非对称流FFF（AsFlFFF）是场流分级分离（FFF）的成员，可以根据其流体动力学直径将大小从纳米级到微米级的颗粒分离，较小的颗粒比较大的颗粒更早地被洗脱。对于球体，如果对AsFlFFF条件进行了优化，则FFF理论可以预测给定直径的洗脱时间。在本文中，我们旨在使用AsFlFFF通道比较具有三种不同形态的金纳米颗粒的洗脱行为，并对其在AsFlFFF中分离的机理进行全面描述。此外，比较了从AsF1FFF获得的粒径与从其他技术例如透射电子显微镜（TEM）和动态光散射获得的粒径。在这项研究中，金纳米球（GNS），金纳米三角形（GNT），合成了金纳米棒（GNR）。TEM数据表明，GNS和GNT的平均粒径和边缘长度分别为51和35nm，而GNR的长度为47nm。尽管GNS的直径接近GNR的长度，但是在相同的ASF1FF条件下，GNS的洗脱时间（4.45分钟）比GNR的洗脱时间（3.70分钟）长得多。另外，即使GNT的洗脱时间小于GNR，其洗脱时间也比GNR长。这可能归因于GNR达到的平衡位置比GNS远离通道的积累壁，导致洗脱时间比GNS早。GNT粒子的形状与球体非常相似，并且其行为可能比GNR更接近球体。