Biomedical Engineering Reference
In-Depth Information
Fig. 30
Various SLN preparation methods
6.2.1 High Shear Homogenisation and Ultrasound
These are the techniques which were first utilized to synthesize solid lipid nano-
particles where the drugs are added to the melted lipid at temperature above the
melting point. Hot oil in water (o/w) emulsion is obtained as the hot lipid melt is
dispersed in an aqueous surfactant solution with constant stirring. The tempera-
ture of the surfactant solution should be same as that of the hot lipid melt and fur-
ther it is subjected to ultrasonication using a probe sonicator forming drug loaded
SLN. What makes this technique highly effective and simple is no requirement
of organic solvents to formulate SLNs with poorly soluble drugs (Sharma et al.
2010). In a recent study, curcumin was encapsulated in solid lipid nanoparticles
and realized that this technique is cheaper and simpler as compared to the other
techniques (Puglia et al. 2013). But the drawback lies in the fact that this method
arises with one population in micro-meter range. In addition to this, there is a
problem of metal contamination when ultrasonication is used for longer time as in
case of high lipid concentration samples.
6.2.2 High Pressure Homogenisation Technique
High pressure homogenisation is a very old and efficient technique which has been
used since 1950s especially in large scale production of SLN. Depending upon
the different batch sizes, high pressure homogenizers of different types can be
