ABSTRACT
Ulta performance liqiuid chromatography-triple quadrupole tandem mass spectrometry ( UPLC-MS/MS) was used to monitor the relative levels of bufadienolides in toad venom in normal and bensulfuron-polluted groups. Methanol extract of toad venom was separated by UPLC ( ODS-C18 ) using a gradient elution of water contains 0. 1% formic acid and acetonitrile. Mass spectrometry was used in an ESI source operated in positive ion and MRM mode. The parameters in the source were set as follows: capillary voltage 3. 0 kV; sampling cone voltage 30 V; and desolvation temperature 500℃. In this method, external calibrations of 6 standards were typically constructed (R2=0. 9953-0. 9992). The LOD was 0. 42-4. 86 ng/mL. Intra- and inter-day precision was 3. 8%-6. 8% and 4. 0%-8. 8%, respectively. The recovery of standard was evaluated by spiking the standard compound into toad venom. Their average recoveries were 96. 9%-109. 6%, and RSDs were 2. 0%-8. 1%. This method was further employed into monitoring the levels of 36 bufadienolides. The levels of more than 20 bufadienolides were greatly different after bensulfuron pollution, suggesting that the bensulfuron pollution could change the chemical expression pattern of bufadienolides in toad venom.