Table 4.

Continuous purification of DOPE:DOTAP liposomes loaded with protein (ovalbumin).

	Liposome w/o OVA after SHM	Liposome with OVA in collection vial	Liposome with OVA after three passes through TFF*
Size (nm)	62.8 ± 1.9	88.5 ± 5.7	89.3 ± 10.9
Polydispersity	0.44 ± 0.02	0.45 ± 0.01	0.42 ± 0.02
Zeta potential (mV)	83.9 ± 3.5	43.6 ± 1.6	69.2 ± 6.1
Loading (%)	N/A	N/A	23.9 ± 0.8
Effec. ethanol (% v/v)	N/A	15.0 ± 6.9	4.1 ± 1.5

The lipids were included in the ethanol stream and liposome formation was performed in a SHM, operated at 2 mL min⁻¹ and a ratio of 1:3 solvent:aqueous solution. Protein was added post-liposome formation. OVA = ovalbumin, N/A = not applicable.

^*After each pass a volume of pure buffer was added to the retentate, keeping the level of liquid constant.