ABSTRACT
<p><b>OBJECTIVE</b>To develop a RP-HPLC method to determine plumbagin in Plumbago zeylanica, and to investigate contents of plumbagin in different parts of. P. zeylanica.</p><p><b>METHOD</b>The analysis was carried out at 30 degrees C on a Kromasil C18, column eluted with a mobile phase consisting of a mixture of methanol-water (65: 35). The flow rate was 1 mL x min(-1), the detector wavelength was 213 nm.</p><p><b>RESULT</b>The calibration curve was linear within the concentration ranges of 0.020 8-0. 104 microg (r = 0. 9999). The average recovery was 98.7%. The contents in the root, stem and leaf were 0.394 5%, 0.050 8%, 0.031 4% respectively.</p><p><b>CONCLUSION</b>This method is simple, accurate, replicate and suitable for the determination of plumbagin in P. zeylanica.</p>