Objective: To investigate pharmacokinetics process of the major components of the extract Corydalis tetrahydropalmatine (tetrahydropalmatine

THP)and d-corydaline (corydaline

CDL)in rats. Method: Using LC-MS/MS to measure plasma concentration at different time after ig administration concentration of Corydalis extracts was determined

WinNonlin software was used to calculate pharmacokinetic parameters. Result: ESI (+)ions under the condition of using MRM mode with m/z370-354

m/z 356-340 was used to detecte CDL

THP

while the m/z 306-140 was used to detect the internal standard anisodamine (anisodaminehydrochloride

ADM). In the range of 1.13-565

1.5-750 ng ·mL-1

CDL

THP showed good linearity

high

medium and low recovery rates of THP

and CDL

day and inter-day precision met the demands of quantification

Cmax were (84.3±9.2)

(157.3±99.6)

(497.1±71.3)ng ·mL-1 and (30.8±1.3)

(54.4±22.7)

(91.2±15.4)ng ·mL-1

Tmax were (54.8±6.9)

(119.2±5.7)

(62.5±7.5)min and (31.5±0.07)

(65.6±10.6)

(111.5±4.2)min. Conclusion: LC-MS/MS had good selectivity

high sensitivity for the determination of plasma sample.