HPLC determination of content and entrapment efficiency of oridonin nanostructured lipid carriers

Objectives:To establish HPLC method to determine the drug content and entrapment efficiency of oridonin nanostructured lipid carriers.Methods:Using methanol-water(52∶48) as mobile phase,the separation was performed on a Kromasil C18 column(4.60 mm×150 mm,5 μm)at a flow rate of 1.0 mL·min-1.The detection wavelength was 242 nm and the column temperature was 25 ℃.Results:Regression analysis of peak area against oridonin concentration showed good straight line fit over the range examined:1.0-100 μg·mL-1 (r=0.9998,n=7).The entrapment efficiency of oridonin nanostructured lipid carriers was (68.2±0.60)%.Conclusions:This method was proved to be simple,accurate,sensitive and applicable for determination of drug content and entrapment efficiency of oridonin nanostructured lipid carriers.