Production Techniques - Lipid Nanoparticles: Production, Characterization and Stability - page 26

Table 3.1 (continued)
Production technique Mechanism of particle formation Advantages Disadvantages

Shear between adjacent particles
Formation, growth and implosive
collapse of bubbles due to cavitation
forces

Use of organic solvents can be avoided
Use of large amounts of surfactants can be avoided
Simple technique with lower production cost
Higher energy inputs

Unsuitable for higher lipid
contents
High polydispersity
Physical instability due to high
shearing
Metal contamination due to
ultrasonication
Poor encapsulation eficiency

High shear homogeniza-
tion and/or ultrasonication

Membrane contactor
method

Lipid/oil phase infuses through
membrane pores into the tangen-
tially lowing aqueous phase to form
droplets
Oil droplets crystallize to form lipid
nanoparticles

Controlled particle size with selection of membrane
with correct pore size
Simple to scale-up

Clogging of membrane pores;
frequent replacement or clean-
ing procedures

Parallel processes of supercriti-
cal luid extraction (diffusion) of
organic solvent from emulsions and
lipid dissolution
Expansion of organic phase; leads to
lipid crystallization

Eficient
Rapid and eficient solvent removal
Monodispersity
Removal of low molecular weight impurities is easy
with supercritical luids
Supercritical luid carbon dioxide causes plasticiza-
tion of lipid structures; thermodynamically stable
lipid nanoparticle dispersions
Supercritical luid lower melting point of lipids; suit-
able for thermo-sensitive drugs

Use of organic solvents
Sophisticated equipment
required

Supercritical luid extrac-
tion of emulsions

(continued)