Optimization of nanostructured lipid carriers for lutein delivery

Nanostructured lipid carrier (NLC) systems were developed using response surface methodology to optimize the concentrations of lipophilic and hydrophilic surfactants based on the size of the resulting NLC. From preliminary experiments, a formulation composed of Precirol, Myverol, and Pluronic formed a stable NLC dispersion. Concentrations of the surfactants, Myverol and Pluronic, were optimized by a central composite design and response surface methodology. Lutein (phylloquinone) was used as a lipophilic drug in the NLC system. The particle size and polydispersion index of the NLC were measured using photon correlation spectroscopy. The ultrasonication duration and drug load were found to significantly impact the particle size of the NLCs prepared. The prepared NLCs were examined by differential scanning calorimetry (DSC), X-ray diffraction (XRD), and transmission electron microscopy (TEM) and found to have an imperfect crystalline lattice and a spherical morphology. The lutein-loaded NLCs had high release rates of the drug in simulated intestinal fluid compared to simulated gastric fluid using modified Franz diffusion cells. Sustained-release lutein delivery was achieved using NLC technology. (C) 2009 Elsevier B.V. All rights reserved.