Objective: To establish the method of LC-MS for evaluating helicid and gastrodin plasma drug concentration

and investigate whether there was a interaction between helicid and gastrodin in rabbitsr. Method: Agilent C18 column (4.6 mm×150 mm

1.7 μm)

mobile phase of methanol-water (0.1% formic acid) gradient elution

triple quadrupole mass spectrometry electrospray ionization (ESI) ion source

multiple reaction monitoring (MRM) mode were used

ionization mode was the negative mode. 18 rabbits were divided into 3 groups

LC-MS method was used to measure the blood drug concentration data

the pharmacokinetic software DAS 3.0 was used calculate kinetic parameters in rabbits

and compare their plasma drug concentration in a single and a simultaneous administration. Result: LC-MS method had the characteristics of rapid

sensitive

and strong specificity

helicid was within the concentration range of 0.125-1.00 mg·L-1

gastrodin was in the concentration range of 0.25-1.50 mg·L-1

the ratio of concentration and peak area had a good linear relationship.Cmax and AUC0→∞ of helicid and gastrodin are both increased. Conclusion: LC-MC method had the characteristics of rapid

sensitive

and strong specificity. Helicid with gastrodin have interactions in rabbits.