Separation and characterization of liposomes using asymmetric flow field-flow fractionation with online multi-angle light scattering detection

• Published in: Journal of Chromatography A Vol. 1636; p. 461798
• Main Authors: Écija-Arenas, Ángela, Román-Pizarro, Vanesa, Fernández-Romero, Juan Manuel
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 11-01-2021
• Subjects: Asymmetrical flow field-flow fractionation (AF4); Cholesterol - chemistry; DLS and TEM comparison; Dynamic Light Scattering; Fractionation, Field Flow - methods; Gold - chemistry; Hydrodynamics; Liposomes; Liposomes - chemistry; Metal Nanoparticles - chemistry; Metal Nanoparticles - ultrastructure; Multi-angle light scattering detector (MALS); Online detection; Online Systems; Particle Size; Particle size distribution; Rheology; Water; Particle size distribution; Multi-angle light scattering detector (MALS); Liposomes; Asymmetrical flow field-flow fractionation (AF4); DLS and TEM comparison; Online detection
• ISSN: 0021-9673; 1873-3778
• DOI: 10.1016/j.chroma.2020.461798

•Different separated liposome populations have been monitored by AF4-MALS.•Populations of three types of liposomes (e-Ls, MLs and Ls-CV) have been studied.•Polydispersity and Z-potential of the liposomes have been studied.•Size distribution obtained has been compared with the results from DLS and TEM.•The best resolution of the technique compared to TEM and DLS has been demonstrated.
Liposomes, mainly formed by phospholipids and cholesterol that entrapped different compounds, were separated and characterized using asymmetric flow field-flow fractionation (AF4) coupled with a multi-angle light scattering detector (MALS). AF4 allows the separation of liposomes according to their hydrodynamic size, and the particle size can be estimated directly by their elution time. Besides, different synthesized liposome suspensions of liposomes with different species encapsulated in different places in liposomes were prepared with analytical purposes to be studied. These liposomes were: empty liposomes (e-Ls), magnetoliposomes (MLs) with Fe3O4@AuNPs-C12SH inside the lipid bilayer, and long-wavelength fluorophores encapsulated into the aqueous cavity of liposomes (Ls-LWF). The optimization process of the variables that affect the fractionation has been established. The separation effectiveness has been compared with the results achieved with a photon-correlation spectroscopy analyzer based on dynamic light scattering (DLS) and transmission electron microscopy (TEM), used in self-assembly structures characterization. In all cases, three different classes of liposomes have been obtained; two are commonly appaired in all studied samples, while only a third class is characteristic for each of the liposomes. This mean that the proposed methodology could be used for identifying liposomes according to the encapsulated material.