Liposomes: preparation and characterization with a special focus on the application of capillary electrophoresis

Abstract

Liposomes are nowadays a matter of tremendous interest. Due to their amphiphilic character, various substances with different properties can be incorporated into them and they are especially suitable as a model system for controlled transport of bioactive substances and drugs to the final destination in the body; for example, COVID-19 vaccines use liposomes as a carrier of mRNA. Liposomes mimicking composition of various biological membranes can be prepared with a proper choice of the lipids used, which proved to be important tool in the early drug development. This review deals with commonly used methods for the preparation and characterization of liposomes which is essential for their later use. The alternative capillary electrophoresis methods for physico-chemical characterization such as determination of membrane permeability of liposome, its size and charge, and encapsulation efficiency are included. Two different layouts using liposomes to yield more efficient separation of various analytes are also presented, capillary electrochromatography, and liposomal electrokinetic chromatography.

Keywords: Analytical method; Capillary zone electrophoresis; Liposomes; Nanoparticles.

Fig. 1

Release of encapsulated oxaliplatin from PEGylated liposome with increasing sonication time. Reprinted and modified with permission from Ref. [51]

Fig. 2

Electropherograms showing the size-dependent separation of liposomes varying in their size in 3% linear polyacrylamide gel matrix. Numbers in ovals show ionic strength of Tris–HCl background electrolyte. Reprinted and modified with permission from Ref. [53]

Fig. 3

Correlation between the K_lw values of uncharged aromatic compounds obtained from LEKC and predicted by LSER. Reprinted and modified with permission from Ref. [66]