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AAPS PharmSciTech. 2005 June; 6(2): E158–E166.
Published online 2005 September 30. doi:  10.1208/pt060224
PMCID: PMC2750527

Etoposide-loaded nanoparticles made from glyceride lipids: Formulation, characterization, in vitro drug release, and stability evaluation


The aim of the study was to prepare etoposide-loaded nanoparticles with glyceride lipids and then characterize and evaluate the in vitro steric stability and drug release characteristics and stability. The nanoparticles were prepared by melt emulsification and homogenization followed by spray drying of nanodispersion. Spray drying created powder nanoparticles with excellent redispersibility and a minimal increase in particle size (20–40 nm). Experimental variables, such as homogenization pressure, number of homogenization cycles, and surfactant concentration, showed a profound influence on the particle size and distribution. Spray drying of Poloxamer 407-stabilized nanodispersion lead to the formation of matrix-like structures surrounding the nanoparticles, resulting in particle growth. The in vitro steric stability test revealed that the lipid nanoparticles stabilized by sodium tauroglycocholate exhibit excellent steric stability compared with Poloxamer 407. All 3 glyceride nanoparticle formulations exhibited sustained release characteristics, and the release pattern followed the Higuchi equation. The spray-dried lipid nanoparticles stored in black polypropylene containers exhibited excellent long-term stability at 25°C and room light conditions. Such stable lipid nanoparticles with in vitro steric stability can be a beneficial delivery system for intravenous administration as long circulating carriers for controlled and targeted drug delivery.

Keywords: lipid nanoparticles, high-pressure homogenization, spray drying, Poloxamer 407, steric stability

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Selected References

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