TY - JOUR TI - Development and characterization of lipid based nanosystems of quercetin for topical delivery DO - https://doi.org/doi:10.7282/T3765D5F PY - 2012 AB - The presence of large amounts of reactive oxygen species (ROS) leads to oxidative stress that can damage cell membranes, lead to DNA breakage and inactivation of free radical scavenger enzymes, eventually resulting in skin damage. The natural flavonoid quercetin (3, 3’, 4’, 5,7-pentahydroxyflavone) has been shown to have the highest anti-radical activity, along with the ability to act as a scavenger of free radicals and an inhibitor of lipid peroxidation. In this research work, lipid based nanosystems of quercetin have been developed using lipids and surfactants considered acceptable in topical formulations and evaluated for topical delivery of quercetin. Systematic screening of the formulation and process parameters led to the development of a physically stable solid lipid (glyceryl dibehenate) based nanosystem using a probe ultrasonication method. Further optimization of the formulation included substitution of a part of the solid lipid (glyceryl dibehenate) with a liquid lipid (oleic acid) to generate nanostructured lipid carriers (NLC). High pressure homogenization, a method widely used in the pharmaceutical industry to generate nanoparticles, was also evaluated as a manufacturing process for these lipid based nanosystems. Transmission electron microscopy (TEM) studies showed spherical particles in the nanometer range for all the systems. XRD scans indicated the onset of a partial transformation of glyceryl behenate from the metastable β’ to the more stable βi form for all formulations. In vitro release studies showed a biphasic release profile, characterized by an initial burst release followed by a more controlled release pattern. Skin permeation studies using full thickness human skin showed a statistically significant increase in the amount of quercetin retained in the skin from the NLC formulation compared to non-nanosized control formulations, with and without oleic acid. This demonstrated the potential of these lipid based nanosystems to act as suitable agents for the topical delivery of quercetin. Both SLN and NLC formulations were also found to have no genotoxic or cytotoxic effects at the concentrations evaluated. KW - Pharmaceutical Science KW - Quercetin KW - Nanoparticles KW - Lipids--Research LA - eng ER -