Study on determination of triptolide in human plasma by HPLC-MS

OBJECTIVE To establish a method for the determination of triptolide in human plasma by HPLC/MS. METHODS Use Thermo-keystone Hypurity C_(18) column (150×(2.1) mm, 5μm);the mobile phase was methanol-water (30∶70) with a flow rate of (0.2) mL∶min~(-1); column temperature (40 ℃). A Finnigan LCQ Deca XP TM with an atmospheric pressure chemical ionization (APCI) source was used as detector and was operated in positive ion mode. Selected reaction monitoring (SRM) was used and transitions selected for quantization were: 343 and 246(m/z), the mass spectrometric conditions were as follows: the temperatures of the heated capillary was (200 ℃). Nitrogen was used as sheath and auxiliary gas with a flow rate of 50 and 15 mL.min~(-1 ). RESULTS The calibration curve was linear over the concentration range of (4.1) to (262.0) μg∶L~(-1),the limit of quantization was (2.0)μg∶L~(-1). Within-day and between-day precision expressed by relative standard deviation (RSD) was (1.5%) to (5.6%) and (4.1%) to (7.8%), respectively. CONCLUSION This method is proved to be specific, accurate and sensitive enough to be applied to the determination of triptolide in human plasma