[Preparation of Kushen-Dilong nanoemulsion gel and transdermal characterization in vitro]

To prepare Kushen-Dilong nanoemulsion and nanoemuls-ion gel, and investigate its content, physical and chemical properties. Their transdermal properties in vitro were studied as well.

IPM acted as oil phase, EL35 as surfactant, EtOH as cosurfactant, Pheretima aqueous solution was added dropwise to the oil phase to prepare Kushen-Dilong nanoemulsion at room temperature using magnetic stirring. HPLC was used to determine the content of matrine and oxymatrine in the nanoemulsion. Transmission electron microscopy and laser particle size analyzer was used to determine the shape and size of the nanoemulsion. NP700 was used as substrate to prepare Kushen-Dilong nanoemulsion gel. Franz diffusion cell was used for the nanoemulsion and gel transdermal characteristics in vitro.

The Kushen-Dilong nanoemulsion was O/W nanoemulsion, its uniform particle size was 20.6 nm with roundness appearance and stable content. The steady-state permeation rate of Kushen-Dilong nanoemulsion, nanoemulsion gel, saturated aqueous solution, hydro gel were 0.1484, 0.1183, 0.0306, 0.0321 mg x cm(-2) x h(-1), respectively.

The 24 h cumulative infiltration and infiltration rate of Kushen-Dilong nanoemulsion and nanoemulsion gel were better than the saturated aqueous solution and hydro gel, which could provide a new dosage form for Kushen-Dilong transdermal drug delivery.