Small volume extruder

For the liposome formation lipids (DOPC and DOPE) were mixed in the required ratio, the solvent (chloroform) was removed by evaporation and an appropriate volume of buffer (50 mM Na₂SO₄, 10 mM TRIS, 10 mM MES, 0.6 mM EGTA) was added to reach the final lipid concentration of 0.2 mg/ml. Unilamellar vesicles were obtained using a small-volume extruder (Avanti Polar lipids Inc.) with a 100 nm filter. The liposomes were incubated with each RA at a concentration of 0.5 mM for 15 min at RT. Measurements of the electrophoretic mobility of liposomes in an electrical field were performed by a Malvern Zetasizer Nano ZS device (Malvern, UK) at 25°C and pH 7.32. The obtained velocity data were used for the calculation of electrophoretic mobility of liposomes. The Smoluchowski model was applied to calculate the Zeta-potential.

Lipids were dissolved in chloroform (DPhPC) or a mixture of chloroform and methanol (1:1, v/v; DPPE and modified DPPE) and the solvents were evaporated. Buffer (50 mmol/L Na₂SO₄, 10 mmol/L MES, 10 mmol/L TRIS, 0.6 mmol/L EGTA, pH 7.32) was added to reach a lipid concentration of 0.2 g/L and vortexed (5 min). Large unilamellar vesicles (LUVs) were obtained using a small-volume extruder (Avanti Polar lipids Inc) with a filter size of 200 nm. The electrophoretic mobility of LUVs was measured in an electrical field using a Malvern Zetasizer Nano ZS device (Malvern, UK) at 25°C.