Field-flow fractionation: analysis of macromolecular, colloidal, and particulate materials

Recent Progress in Isolation and Detection of Extracellular Vesicles for Cancer Diagnostics

Extracellular vesicles (EVs) are emerging as one of the many new and promising biomarkers for liquid biopsy of cancer due to their loading capability of some specific proteins and nucleic acids that are closely associated with cancer states. As such, the isolation and detection of cancer-derived EVs offer important information in noninvasive diagnosis of early-stage cancer and real-time monitoring of cancer development. In light of the importance of EVs, over the last decade, researchers have made remarkable innovations to advance the development of EV isolation and detection methods by taking advantage of microfluidics, biomolecule probes, nanomaterials, surface plasmon, optics, and so on. This review introduces the basic properties of EVs and common cancer-derived EV ingredients, and provides a comprehensive overview of EV isolation and detection strategies, with emphasis on liquid biopsies of EVs for cancer diagnostics.

Coupling a gamma-ray detector with asymmetrical flow field flow fractionation (AF4): Application to a drug-delivery system for alpha-therapy

Alpha-particle-emitting radionuclides have been the subject of considerable investigation as cancer therapeutics, since they have the advantages of high potency and specificity. Among α-emitting radionuclides that are medically relevant and currently available, the lead-212/bismuth-212 radionuclide pair could constitute an in vivo generator. Considering its short half-life (T_1/2 = 60.6 min), ²¹²Bi can only be delivered using labelled carrier molecules that would rapidly accumulate in the target tumor. To expand the range of applications, an interesting method is to use its longer half-life parent ²¹²Pb (T_1/2 = 10.6 h) that decays to ²¹²Bi. The challenge consists in keeping ²¹²Bi bound to the vector after the ²¹²Pb decay. Preclinical and clinical studies have shown that a variety of vectors may be used to target alpha-emitting radionuclides to cancer cells. Nanoparticles, notably liposomes, allow combined targeting options, achieving high specific activities, easier combination of imaging and therapy and development of multimodality therapeutic agents (e.g., radionuclide therapy plus chemotherapy). The aim of this work consists in assessing the in vitro stability of ²¹²Pb/²¹²Bi encapsulation in the liposomes. Indeed, the release of the radionuclide from the carrier molecules might causes toxicity to normal tissues. To reach this goal, Asymmetrical Flow Field-Flow Fractionation (AF4) coupled with a Multi-Angle Light Scattering detector (MALS) was used and coupling with a gamma (γ) ray detector was developed. AF4-MALS-γ was shown to be a powerful tool for monitoring the liposome size together with the incorporation of the high energy alpha emitter. This was successfully extended to assess the stability of ²¹²Bi-radiolabelled liposomes in serum showing that more than 85% of ²¹²Pb/²¹²Bi is retained after 24 h of incubation at 37 °C.

Preservation of the soft protein corona in distinct flow allows identification of weakly bound proteins

Nanocarriers that are used for targeted drug delivery come in contact with biological liquids and subsequently proteins will adsorb to the nanocarriers' surface to form the so called 'protein corona'. The protein corona defines the biological identity and determines the biological response towards the nanocarriers in the body. To make nanomedicine safe and reliable it is required to get a better insight into this protein corona and, therefore, the adsorbed proteins have to be characterized. Currently, centrifugation is the common method to isolate the protein corona for further investigations. However, with this method it is only possible to investigate the strongly bound proteins, also referred to as 'hard protein corona'. Therefore, we want to introduce a new separation technique to separate nanoparticles including the soft protein corona containing also loosely bound proteins for further characterization. The used separation technique is the asymmetric flow field-flow fractionation (AF4). We were able to separate the nanoparticles with proteins forming the soft protein corona and were able to show that in our system only the hard protein corona directly influenced the cell uptake behavior.

STATEMENT OF SIGNIFICANCE

Currently, there is an ongoing debate whether only strongly bound proteins (hard corona) or also loosely bound proteins (soft corona) contribute to the biological identity of nanocarriers, because up to now isolation of the soft corona was not possible. Here, asymmetric flow field-flow fractionation was used to isolate nanoparticles with a preserved soft corona from the biological medium. This enabled the characterization of the soft corona composition and to evaluate its influence on cellular uptake. For our system we found that only the strongly bound proteins (hard corona) determined cell internalization. This method can now be used to evaluate the impact of the soft corona further and to characterize nanomaterials that cannot be separated from blood plasma by other means.

Asymmetrical flow field-flow fractionation in purification of an enveloped bacteriophage ϕ6

Basic and applied virus research requires specimens that are purified to high homogeneity. Thus, there is much interest in the efficient production and purification of viruses and their subassemblies. Advances in the production steps have shifted the bottle neck of the process to the purification. Nonetheless, the development of purification techniques for different viruses is challenging due to the complex biological nature of the infected cell cultures as well as the biophysical and -chemical differences in the virus particles. We used bacteriophage ϕ6 as a model virus in our attempts to provide a new purification method for enveloped viruses. We compared asymmetrical flow field-flow fractionation (AF4)-based virus purification method to the well-established ultracentrifugation-based purification of ϕ6. In addition, binding of ϕ6 virions to monolithic anion exchange columns was tested to evaluate their applicability in concentrating the AF4 purified specimens. Our results show that AF4 enables one-hour purification of infectious enveloped viruses with specific infectivity of ~1 × 10¹³ PFU/mg of protein and ~65-95% yields. Obtained purity was comparable with that obtained using ultracentrifugation, but the yields from AF4 purification were 2-3-fold higher. Importantly, high quality virus preparations could be obtained directly from crude cell lysates. Furthermore, when used in combination with in-line light scattering detectors, AF4 purification could be coupled to simultaneous quality control of obtained virus specimen.

Flow field-flow fractionation and multi-angle light scattering as a powerful tool for the characterization and stability evaluation of drug-loaded metal-organic framework nanoparticles

Asymmetric flow field-flow fractionation (AF4) coupled with UV-Vis spectroscopy, multi-angle light scattering (MALS) and refractive index (RI) detection has been applied for the characterization of MIL-100(Fe) nanoMOFs (metal-organic frameworks) loaded with nucleoside reverse transcriptase inhibitor (NRTI) drugs for the first time. Empty nanoMOFs and nanoMOFs loaded with azidothymidine derivatives with three different degrees of phosphorylation were examined: azidothymidine (AZT, native drug), azidothymidine monophosphate (AZT-MP), and azidothymidine triphosphate (AZT-TP). The particle size distribution and the stability of the nanoparticles when interacting with drugs have been determined in a time frame of 24 h. Main achievements include detection of aggregate formation in an early stage and monitoring nanoMOF morphological changes as indicators of their interaction with guest molecules. AF4-MALS proved to be a useful methodology to analyze nanoparticles engineered for drug delivery applications and gave fundamental data on their size distribution and stability. Graphical abstract ᅟ.

Approach to classify, separate, and enrich objects in groups using ensemble sorting

The sorting of objects into groups is a fundamental operation, critical in the preparation and purification of populations of cells, crystals, beads, or droplets, necessary for research and applications in biology, chemistry, and materials science. Most of the efforts exploring such purification have focused on two areas: the degree of separation and the measurement precision required for effective separation. Conventionally, achieving good separation ultimately requires that the objects are considered one by one (which can be both slow and expensive), and the ability to measure the sorted objects by increasing sensitivity as well as reducing sorting errors. Here we present an approach to sorting that addresses both critical limitations with a scheme that allows us to approach the theoretical limit for the accuracy of sorting decisions. Rather than sorting individual objects, we sort the objects in ensembles, via a set of registers which are then in turn sorted themselves into a second symmetric set of registers in a lossless manner. By repeating this process, we can arrive at high sorting purity with a low set of constraints. We demonstrate both the theory behind this idea and identify the critical parameters (ensemble population and sorting time), and show the utility and robustness of our method with simulations and experimental systems spanning several orders of scale, sorting populations of macroscopic beads and microfluidic droplets. Our method is general in nature and simplifies the sorting process, and thus stands to enhance many different areas of science, such as purification, enrichment of rare objects, and separation of dynamic populations.

Advancements in microfluidic technologies for isolation and early detection of circulating cancer-related biomarkers

Isolation of circulating biomarkers using microfluidic devices for cancer diagnosis.

Explicit role of ionic strength in retention behavior of polystyrene latex particles in sedimentation field-flow fractionation: Slip boundary model

We investigate an explicit role of the ionic strength in the retention behaviors of polystyrene (PS) latex particles in sedimentation field-flow fractionation (SdFFF) by hinging upon the retention theory recently developed [1] asR=(R_o+v_b^*)/(1+v_b^*). Here R is an experimental retention ratio, and R_o is the analytical expression of the standard retention theory based on the parabolic flow velocity. The reduced boundary velocityv_b^* is expressed in terms of the ionic strength I of the carrier liquid as v_b^*=v_b,o^*/(1+εI), where v_b,o^*=0.070and ε=60 mM^-1 for all the PS latex systems under investigation. We then apply this to study the explicit ionic strength effect on the retention behaviors of PS beads of 200, 300, 400, and 500nm, respectively. As a primary result, the strong dependence of the retention ratio on the ionic strength can be quantitatively accounted for in an excellent accuracy: The slip effect at the channel surface is significant, particularly when I≲0.5mM, without showing any distinguishable dependence on the specific additives to control I, such as FL-70, SDS, NaNO₃, and NaN₃. Based on the present study, we put forward an experimental means to estimate the ionic strength of an aqueous solution using an FFF technique.

Anisotropic thermophoresis

Colloidal migration in a temperature gradient is referred to as thermophoresis. In contrast to particles with a spherical shape, we show that elongated colloids may have a thermophoretic response that varies with the colloid orientation. Remarkably, this can translate into a non-vanishing thermophoretic force in the direction perpendicular to the temperature gradient. Opposite to the friction force, the thermophoretic force of a rod oriented with the temperature gradient can be larger or smaller than when oriented perpendicular to it. The precise anisotropic thermophoretic behavior clearly depends on the colloidal rod aspect ratio, and also on its surface details, which provides an interesting tunability to the devices constructed based on this principle. By means of mesoscale hydrodynamic simulations, we characterize this effect for different types of rod-like colloids.

Microfluidic co-flow of Newtonian and viscoelastic fluids for high-resolution separation of microparticles

The microfluidic passive control of microparticles largely relies on the hydrodynamic effects of the carrier media such as Newtonian fluids and viscoelastic fluids. Yet the viscoelastic/Newtonian interfacial effect has been scarcely investigated, especially for high-resolution particle separation. Here we report a microfluidic co-flow of Newtonian (water or PBS) and viscoelastic fluids (PEO) for the size-dependent separation of microparticles. The co-flow condition generates a stable viscoelastic/Newtonian interface, giving rise to the wall-directed elastic lift forces that compete with the center-directed lift forces, and efficiently hinders the migration of microparticles from the Newtonian to the viscoelastic fluid in a size-dependent manner. An almost complete separation of a binary mixture of 1 μm and 2 μm polystyrene particles is achieved by the co-flow of water and a very dilute PEO solution (100 ppm), whereas the sole use of water or PEO could not lead to an efficient separation. This co-flow microfluidic system is also applied for the separation of Staphylococcus aureus (1 μm) from platelets (2-3 μm) with >90% efficiencies and purities.

Convective and diffusive effects on particle transport in asymmetric periodic capillaries

We present here results of a theoretical investigation of particle transport in longitudinally asymmetric but axially symmetric capillaries, allowing for the influence of both diffusion and convection. In this study we have focused attention primarily on characterizing the influence of tube geometry and applied hydraulic pressure on the magnitude, direction and rate of transport of particles in axi-symmetric, saw-tooth shaped tubes. Three initial value problems are considered. The first involves the evolution of a fixed number of particles initially confined to a central wave-section. The second involves the evolution of the same initial state but including an ongoing production of particles in the central wave-section. The third involves the evolution of particles a fully laden tube. Based on a physical model of convective-diffusive transport, assuming an underlying oscillatory fluid velocity field that is unaffected by the presence of the particles, we find that transport rates and even net transport directions depend critically on the design specifics, such as tube geometry, flow rate, initial particle configuration and whether or not particles are continuously introduced. The second transient scenario is qualitatively independent of the details of how particles are generated. In the third scenario there is no net transport. As the study is fundamental in nature, our findings could engender greater understanding of practical systems.

Nanomaterials in Food Products: A New Analytical Challenge

This chapter focuses on the problem of detecting, characterizing, and determining the concentration of nanomaterials in foods and other biological matrices. After providing an overview of the unique challenges associated with nanoparticle metrology in complex media, sample pretreatment methods (including extraction, digestion, and inline chromatographic separation), imaging analysis, and nanomaterial quantification methods are presented in detail. The chapter also addresses numerous methods under development, including atmospheric scanning electron microscopy, single-particle inductively coupled plasma mass spectrometry, immunological detection methods, and optical techniques such surface plasmon resonance. The chapter concludes with an overview of the research needs in this area.

Thermophoretic migration of vesicles depends on mean temperature and head group chemistry

A number of colloidal systems, including polymers, proteins, micelles and hard spheres, have been studied in thermal gradients to observe and characterize their driven motion. Here we show experimentally the thermophoretic behaviour of unilamellar lipid vesicles, finding that mobility depends on the mean local temperature of the suspension and on the structure of the exposed polar lipid head groups. By tuning the temperature, vesicles can be directed towards hot or cold, forming a highly concentrated region. Binary mixtures of vesicles composed of different lipids can be segregated using thermophoresis, according to their head group. Our results demonstrate that thermophoresis enables robust and chemically specific directed motion of liposomes, which can be exploited in driven processes.

Thermal gradients are shown to provide a robust and chemically specific driving force to liposomes. Here the authors show controlled direction of migration of unilamellar lipid vesicles by varying the temperature in the suspension and the exposed polar lipid head groups.

Effect of cationic monomer content on polyacrylamide copolymers by frit-inlet asymmetrical flow field-flow fractionation/multi-angle light scattering

In this study, ultrahigh-molecular-weight (MW) (>10⁷Da) cationic polyacrylamides (C-PAMs), which are water-soluble polymers used in waste water treatment, were characterized using frit-inlet asymmetrical flow field-flow fractionation coupled with multi-angle light scattering and differential refractive detection. C-PAMs copolymerized with acryloxyethyltrimethyl ammonium chloride (DAC) were prepared by varying the feed amount of cationic monomer, polymerization method (solution vs. emulsion), and degree of branching. The MW of the copolymers prepared using emulsion polymerization (10⁷-10⁹Da) was generally larger than that of copolymers prepared using solution polymerization (4×10⁷-10⁸Da). When the amount of cationic monomer was increased from 10 to 55mol% in solution polymerization, hydrophobic contraction of the core induced formation of more compact C-PAMs. The copolymers prepared using emulsion polymerization formed highly aggregated or supercoil structures owing to increased intermolecular hydrophobic interaction when less cationic monomer was used. However, the MW decreased with increased cationic group content. In addition, C-PAMs larger than ∼10⁸Da prepared using the emulsion method were separated by steric/hyperlayer elution mode while those in the 10⁷-10⁸Da range were analyzed in either normal or steric/hyperlayer mode depending on the decay patterns of field programming. Moreover, branched copolymers were found to be resolved with different elution modes under the same field decay pattern depending on the degree of branching: steric/hyperlayer for low-branching and normal for high-branching C-PAMs.

Rejection of Commonly Used Electrolytes in Asymmetric Flow Field Flow Fractionation: Effects of Membrane Molecular Weight Cutoff Size, Fluid Dynamics, and Valence of Electrolytes

Asymmetric flow field flow fractionation (AF4) is an efficient size-based separation technique for the characterization of submicron size particulates. In AF4, membranes having various molecular weight cutoff sizes are used as a barrier to retain particles while allowing the carrier fluid containing electrolytes to permeate. Here, we have hypothesized that electrolyte rejection by the barrier membrane leads to the accumulation of electrolytes in the channel during operation. Electrolyte accumulation can cause various adverse effects that can lead to membrane fouling. An instrument setup containing a conductivity detector was assembled, and the rejection of commonly used carrier electrolytes such as trisodium citrate, ethylenediaminetetraacetic acid, sodium chloride, and ammonium carbonate was evaluated by varying the concentration, cross-flow rate, focusing flow rate, membrane material type, and cutoff sizes. The results showed that electrolyte rejection increased with a decrease in the electrolyte concentration and the molecular weight cutoff size (pore size) or with an increase in the charge state of the anion in the carrier electrolytes. We proposed an electrostatic repulsion-based rejection mechanism and verified it with the measurement of the rejection rate while varying the electrolyte concentration in the running media.

Characterization of cereal β-glucan extracts from oat and barley and quantification of proteinaceous matter

An extraction method for mixed-linkage β-glucan from oat and barley was developed in order to minimize the effect of extraction on the β-glucan structure. β-Glucan were characterized in terms of molecular size and molar mass distributions using asymmetric flow field-flow fractionation (AF4) coupled to multiangle light scattering (MALS), differential refractive index (dRI) and fluorescence (FL) detection. The carbohydrate composition of the extracts was analysed using polysaccharide analysis by carbohydrate gel electrophoresis (PACE) and high-performance anion-exchange chromatography (HPAEC). Whether there were any proteinaceous moieties linked to β-glucan was also examined. Purified extracts contained 65% and 53% β-glucan for oats and barley, respectively. The main impurities were degradation products of starch. The extracts contained high molecular weight β-glucan (105-108 g/mol) and large sizes (root-mean-square radii from 20 to 140 nm). No proteins covalently bound to β-glucan were detected; therefore, any suggested functionality of proteins regarding the health benefits of β-glucan can be discounted.

Size Dependent Lipidomic Analysis of Urinary Exosomes from Patients with Prostate Cancer by Flow Field-Flow Fractionation and Nanoflow Liquid Chromatography-Tandem Mass Spectrometry

Exosomes are membrane-bound extracellular vesicles involved in intercellular communication and tumor cell metastasis. In this study, flow field-flow fractionation (FlFFF) was utilized to separate urinary exosomes by size, demonstrating a significant difference in exosome sizes between healthy controls and patients with prostate cancer (PCa). Exosome fractions of different sizes were collected for microscopic analysis during an FlFFF run and evaluated with exosome marker proteins using Western blot analysis. The results indicated that exosomes of different sizes originated from different types of cells. Collected exosome fractions were further examined using nanoflow ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry (nUPLC-ESI-MS/MS) for lipidomic analysis. A total of 162 lipids (from 286 identified) were quantified using a selected reaction monitoring (SRM) method. The overall amount of lipids increased by 1.5- to 2-fold in patients with PCa and degree of increase was more significant in the smaller fractions (diameter <150 nm) than in the larger ones (diameter >150 nm) some classes of lipids. In addition, neutral lipids like diacylglycerol (DAG) and triacylglycerol (TAG) decreased in all exosomes without size dependency. Moreover, a dramatic increase in 22:6/22:6-phosphatidylglycerol (PG) was observed and significant decrease in (16:0,16:0)- and (16:1, 18:1)-DAG species (nearly 5-fold) and high abundant TAG species (>2.5-fold) was observed in patients with PCa. The results of this study indicate that FlFFF can be employed for the high-speed screening of urinary exosome sizes in patients with PCa and lipidomic analysis of the fractionated exosomes has potential for developing and distinguishing biomarkers of PCa.

Advancements in microfluidics for nanoparticle separation

Nanoparticles have been widely implemented for healthcare and nanoscience industrial applications. Thus, efficient and effective nanoparticle separation methods are essential for advancement in these fields. However, current technologies for separation, such as ultracentrifugation, electrophoresis, filtration, chromatography, and selective precipitation, are not continuous and require multiple preparation steps and a minimum sample volume. Microfluidics has offered a relatively simple, low-cost, and continuous particle separation approach, and has been well-established for micron-sized particle sorting. Here, we review the recent advances in nanoparticle separation using microfluidic devices, focusing on its techniques, its advantages over conventional methods, and its potential applications, as well as foreseeable challenges in the separation of synthetic nanoparticles and biological molecules, especially DNA, proteins, viruses, and exosomes.

Effects of Bni5 Binding on Septin Filament Organization

Septins are a protein family found in all eukaryotes (except higher plants) that have roles in membrane remodeling and formation of diffusion barriers and as a scaffold to recruit other proteins. In budding yeast, proper execution of cytokinesis and cell division requires the formation of a collar of circumferential filaments at the bud neck. These filaments are assembled from apolar septin hetero-octamers. Currently, little is known about the mechanisms that control the arrangement and dynamics of septin structures. In this study, we utilized both Förster resonance energy transfer and electron microscopy to analyze the biophysical properties of the septin-binding protein Bni5 and how its association with septin filaments affects their organization. We found that the interaction of Bni5 with the terminal subunit (Cdc11) at the junctions between adjacent hetero-octamers in paired filaments is highly cooperative. Both the C-terminal end of Bni5 and the C-terminal extension of Cdc11 make important contributions to their interaction. Moreover, this binding may stabilize the dimerization of Bni5, which, in turn, forms cross-filament braces that significantly narrow, and impose much more uniform spacing on, the gap between paired filaments.

Sheathless electrokinetic particle separation in a bifurcating microchannel

Particle separation has found practical applications in many areas from industry to academia. Current electrokinetic particle separation techniques primarily rely on dielectrophoresis, where the electric field gradients are generated by either active microelectrodes or inert micro-insulators. We develop herein a new type of electrokinetic method to continuously separate particles in a bifurcating microchannel. This sheath-free separation makes use of the inherent wall-induced electrical lift to focus particles towards the centerline of the main-branch and then deflect them to size-dependent flow paths in each side-branch. A theoretical model is also developed to understand such a size-based separation, which simulates the experimental observations with a good agreement. This electric field-driven sheathless separation can potentially be operated in a parallel or cascade mode to increase the particle throughput or resolution.

A new analytical platform based on field-flow fractionation and olfactory sensor to improve the detection of viable and non-viable bacteria in food

An integrated sensing system is presented for the first time, where a metal oxide semiconductor sensor-based electronic olfactory system (MOS array), employed for pathogen bacteria identification based on their volatile organic compound (VOC) characterisation, is assisted by a preliminary separative technique based on gravitational field-flow fractionation (GrFFF). In the integrated system, a preliminary step using GrFFF fractionation of a complex sample provided bacteria-enriched fractions readily available for subsequent MOS array analysis. The MOS array signals were then analysed employing a chemometric approach using principal components analysis (PCA) for a first-data exploration, followed by linear discriminant analysis (LDA) as a classification tool, using the PCA scores as input variables. The ability of the GrFFF-MOS system to distinguish between viable and non-viable cells of the same strain was demonstrated for the first time, yielding 100 % ability of correct prediction. The integrated system was also applied as a proof of concept for multianalyte purposes, for the detection of two bacterial strains (Escherichia coli O157:H7 and Yersinia enterocolitica) simultaneously present in artificially contaminated milk samples, obtaining a 100 % ability of correct prediction. Acquired results show that GrFFF band slicing before MOS array analysis can significantly increase reliability and reproducibility of pathogen bacteria identification based on their VOC production, simplifying the analytical procedure and largely eliminating sample matrix effects. The developed GrFFF-MOS integrated system can be considered a simple straightforward approach for pathogen bacteria identification directly from their food matrix. Graphical abstract An integrated sensing system is presented for pathogen bacteria identification in food, in which field-flow fractionation is exploited to prepare enriched cell fractions prior to their analysis by electronic olfactory system analysis.

Elucidating diversity of exosomes: biophysical and molecular characterization methods

Exosomes are cell-secreted nanovesicles present in biological fluids in normal and diseased conditions. Owing to their seminal role in cell-cell communication, emerging evidences suggest that exosomes are fundamental regulators of various diseases. Due to their potential usefulness in disease diagnosis, robust isolation and characterization of exosomes is critical in developing exosome-based assays. In the last few years, different exosome characterization methods, both biophysical and molecular, have been developed to characterize these tiny vesicles. Here, in this review we summarize: first, biophysical techniques based on spectroscopy (e.g., Raman spectroscopy, dynamic light scattering) and other principles, for example, scanning electron microscopy, atomic force microscopy; second, antibody-based molecular techniques including flow cytometry, transmission electron microscopy and third, nanotechnology-dependent exosome characterization methodologies.

New Method for Sorting Endothelial and Neural Progenitors from Human Induced Pluripotent Stem Cells by Sedimentation Field Flow Fractionation

Human induced pluripotent stem cells (hiPSc) are a very useful solution to create and observe the behavior of specific and usually inaccessible cells, such as human motor neurons. Obtained from a patient biopsy by reprograming dermal fibroblasts (DF), hiPSc present the same properties as embryonic stem cells and can generate any cell type after several weeks of differentiation. Today, there are numerus protocols which aim to control hiPSC differentiation. The principal challenge is to obtain a sufficiently enriched specific cell population to study disease pathophysiology and to provide a good model for further investigation and drug screening. The differentiation process is very costly and time-consuming, because many specific factors and different culture media must be used. In this study, we used Sedimentation Field Flow Fractionation (SdFFF) to prepare enriched populations derived from hiPSc after only 10 days of culture in a classical medium. Based on phenotypic and proteomic characterization, "hyperlayer" elution resulted in a fraction expressing markers of endothelial progenitors while another fraction expressed markers of neural progenitors. The isolation of subpopulations representing various differentiation lineages is of major interest for the production of specialized, cell-enriched fractions and in the preparation of increasingly complex models for the development of new therapeutic tools.