Mean pore size, membrane emulsification

The most suitable membrane for emulsification is the so-called Shirasu porous glass (SPG) membrane. This membrane can be fabricated with a wide range of mean pore sizes (0.05-20 xm), with a uniform pore size distribution (PSD), and with a wall porosity between 50 and 60%. Hydrophobic modification of SPG membrane can be easily carried out by surface coating with silicone resin. 

FIGURE 16.1S Influence of transmembrane-to-capillary pressure ratio on droplet size distribution for emulsification using a SPG membrane with the mean pore size of 4.8 p,m. (From Vladisavljevic, G.T. and Schubert, H., J. Membr. Set, 225 (1-2), 15-23, 2003. With permission.)... 

Figure 6.17 SEM photographs and size distribution of a W/O solid lipid carrier with a mean size of 8.4zyxonetwothreexyzm for oral administration of anticancer drng irinotecan hydrochloride (CPT-11). The carrier was prepared by a temperature-controlled emulsification at 30kPa using SPG membrane with a mean pore size of 11.2zyxonetwothreexyzm, followed by cooling down and filtration of the solidified W/O/W emulsion (Shimizu et al., 2002a).

In premix membrane emulsification, emulsion premixes are pressed through the membrane pores. A phase inversion while passing the membrane is induced if the membrane surface is wetted by the droplet phase of the premix. Thus emulsions of high disperse phase fractions, even above 80%, can be produced at a throughput of up to several tons per square meter of membrane surface per hour. A narrow droplet size distribution requires a low number (2-3) of recirculations through the membrane. The mean droplet size is about twice the pore size [51]. 

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