Production Techniques - Lipid Nanoparticles: Production, Characterization and Stability - page 25

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

Direct coupling of microwaves with
molecules
Lipid crystallization due to rapid
solidiication of microemulsion

Controlled microwave heating
Rapid and eficient heating
Low energy inputs
Shorter duration of preparation
Higher temperature gradients; faster lipid
crystallization

Scalability issues

Microwave-assisted micro-
emulsion technique

Solvent evaporation Lipid crystallization due to solvent

evaporation in an anti-solvent

Sophisticated equipment not required
Highly suitable for thermo-sensitive drugs
Small particle diameters
Simple to scale-up

Toxicological issues due to use
of organic solvents
Particle aggregation in absence
of rapid solvent evaporation
Low lipid content

Double emulsion Lipid crystallization due to solidii-

cation of emulsion

Sophisticated equipment not required
Low energy inputs

Low lipid content

Lipid crystallization due to diffusion
of solvent from internal organic
phase to external aqueous phase

Sophisticated equipment not required
Pharmaceutically accepted organic solvents used;
solvent recycling feasible
Small particle diameters and low polydispersity
Simple to scale-up

Although rare, risk of toxico-
logical risks due to incomplete
evaporation of organic solvents
Low lipid content

Solvent diffusion

Lipid crystallization due to rapid
diffusion of solvent from internal
organic phase to external aqueous
phase

Sophisticated equipment not required
Pharmaceutically accepted organic solvents used;
solvent recycling feasible
Highly eficient and versatile technique
Higher performance
Simple to scale up

Solvent removal dificult; use
of freeze-drying or evaporation-
under-reduced-pressure
Low lipid content

Solvent injection (or
displacement)

(continued)