*7.5.1 Cross flow injection method*

This cross flow is one of large scalable liposome preparation technique with a module with two tubes welded crossly [60–63]. To the cross connecting point, one injection hole is adapted. The used concentration of lipid, injecting hole diameter, injection pressure, flowing rate of buffer and performance of system are important parameters to be considered in preparation of liposomes [62]. A minimum amount of buffer flow rate and lipid concentration with higher injection pressures is needed for batch homogeneity. Reproducibility and scale up data of prepared liposomes with this method showed good results on vesicle size, size distribution, stability and robustness [60].

#### *7.5.1.1 Microfluidization*

Liposomes are prepared by injecting lipid and water phases with microfluidic hydrodynamic focusing (MHF) into a microchannel [64]. Microfluidic flow is a low rate laminar flow with. Uniform mixing is observed when multi flow steams injected into microchannel [64].

## *7.5.2 Membrane contactor*

In recent studies ethanol injection method was used along with membrane contractor for large production of liposomes [67]. The lipid phase contains cholesterol and phospholipid mixed in ethanol. That mixture has to be pressed through membrane using nitrogen gas with pressure below 5 bars. Tangentially aqueous phase was passed through the same membrane into organic phase to form liposomal dispersion. This new process has advantages with simple design, control of liposome size and scale up batch abilities [67].
