Purification and characterization of brazilin from Caesalpinia sappan L. extracts. (A) Preparative HPLC profile of purified brazilin from C. sappan extract. A reverse phase C18 column (4.6 x 250 mm) was used for analysis, and eluted with 100% methanol in isocratic mode with flow rate of 0.5 ml/min and detection wavelength of 280 nm. A near-homogenous peak with a retention time of 7.669 min was observed. (B) MALDI-TOF mass spectra of brazilin from C. sappan L. The optimal collision energy was 45eV in the mass range m/z 100 to m/z 450. The detection voltage and interface temperature were set to 1.60 V and 400°C. Methanol was used as the mobile phase.