Development of Nanostructured Lipid Carrier-Loaded Flavonoid-Enriched Zingiber officinale

Flavonoids, which are bioactive molecules found in Zingiber officinale, have been widely used as antioxidant and anti-inflammatory drugs. The presence of nanostructured lipid carriers (NLCs) as sophisticated delivery systems for bioactive compounds, such as flavonoids, can increase their bioavailability and stability, thus potentially producing better therapeutic effects. This study aimed to develop an anti-inflammatory topical gel using NLC-containing flavonoids derived from Zingiber officinale. The NLC formulation was prepared using stearic acid, a mixture of medium-chain triglycerides and isopropyl myristate, Tween 20, and Span 20 by using a hot homogenization method. The total flavonoid content obtained through sequential maceration stages was 4.04 mg of QUE/g of dry extract. The highest encapsulation efficiency of flavonoid-loaded NLC was observed at a flavonoid, Zingiber officinale extract (ZOE) concentration of 2%. It was found that a ZOE concentration of 0.4% provided excellent stability with a particle size of 302-344 nm and a polydispersity index of 0.14-0.23 after 28 days of observation. Morphological analysis of the ZOE-loaded NLC revealed a stable and well-developed formulation with a fairly uniform distribution. The presence of distinctive and uniformly distributed single particles suggests a promising alternative drug delivery system for conventional topical preparations. ZOE-loaded NLC gel showed solid-like properties and higher quality stability than the gel.