Nanoparticle separation with a miniaturized asymmetrical flow field-flow fractionation cartridge

Abstract

Asymmetrical Flow Field-Flow Fractionation (AF4) is a separation technique applicable to particles over a wide size range. Despite the many advantages of AF4, its adoption in routine particle analysis is somewhat limited by the large footprint of currently available separation cartridges, extended analysis times and significant solvent consumption. To address these issues, we describe the fabrication and characterization of miniaturized AF4 cartridges. Key features of the down-scaled platform include simplified cartridge and reagent handling, reduced analysis costs and higher throughput capacities. The separation performance of the miniaturized cartridge is assessed using certified gold and silver nanoparticle standards. Analysis of gold nanoparticle populations indicates shorter analysis times and increased sensitivity compared to conventional AF4 separation schemes. Moreover, nanoparticulate titanium dioxide populations exhibiting broad size distributions are analyzed in a rapid and efficient manner. Finally, the repeatability and reproducibility of the miniaturized platform are investigated with respect to analysis time and separation efficiency.

Halophilic viruses with varying biochemical and biophysical properties are amenable to purification with asymmetrical flow field-flow fractionation

“…In our study, the highest dilution was observed for the AF4 fractionated 1xviruses and PEG-viruses, whereas little (~2-fold) or no dilution was observed for the culture supernatants. If needed, dilution can be reduced by using thinner spacers, miniaturized channel design or a slot flow option, where the sample-free buffer zone and the sample-containing zone are separately collected (Müller et al 2015;Prestel et al 2006).…”

Advancements in microfluidics for nanoparticle separation

“…63,64 For the purpose of nanoparticle separation, asymmetric flow FFF, with one crossflow filtration membrane on the bottom surface, draws greater interest as it has been demonstrated to separate nanoparticles efficiently, such as for the characterization of gold, 65,66 silver, 67,68 and non-metallic nanoparticles. 69,70 Field flow fractionation has a very high throughput and high separation efficiency, and has been proven to separate particles ranging from several nanometers to 100 μm in size. However, extensive optimization is required as each field flow fractionation method needs specific external field magnitudes, sample types, solvents, or membranes for performing efficient separation.…”

Extracellular Vesicles: Isolation Methods

“…Adding an ultrafiltration step to the ultracentrifugation protocol enables to increase the purity of the isolated vesicles. [44] Commerciallyavailable ultrafiltration columns have already been widely used to isolate EVs from biofluids [45] or culture cell media. [46] However, the recovery rate may decreasedue to the trapping of EVs in the nano-or micropores of the membrane, which also leads to clogging issues.…”

“…Faster diffusing particles (small ones) are eluted earlier by the faster central streamlines compared to larger ones staying near the accumulating wall. Adapted with permission [44]. Copyright 2014, Elsevier.…”