Twenty microliter of the extract sample was injected in a reverse phase HPLC (LC-20AD, Shimadzu, Japan) at a flow rate of 0.8 ml/ min using 25% acetonitrile as the mobile phase. ODS Hypersil gold column (Thermo Scientific) with a particle size of 5 µm was used as the stationary phase at a temperature of 30 °C. Absorbance of camptothecin was measured at 254 nm by a photodiode array detector10 (link). Concentration of camptothecin in the sample was estimated using a standard plot of area vs. known concentration of camptothecin, generated using authentic samples of camptothecin (> 95% purity, Sigma Aldrich, St. Louis, MO, USA ).
Free full text: Click here
