Objective:To investigate the effect of compatibility of Tripterygii Radix et Rhizoma and Paeoniae Radix Alba on the percutaneous absorption of triptolide and two alkaloids(wilforgine and wilforine)

to investigate the mechanism of reducing toxicity of Tripterygii Radix et Rhizoma combined with Paeoniae Radix Alba from the perspective of transdermal transport. Method:The modified Franz diffusion cell was employed

taking in vitro abdominal skin of mice as transdermal barrier

with 20% ethanol physiological saline as receiving medium

the contents of triptolide(mobile phase of acetonitrile-water for gradient elution

detection wavelength at 220 nm)

wilforgine and wilforine[mobile phase of acetonitrile-0.1% phosphoric acid(57:43)

detection wavelength at 230 nm]in the receiving liquid was determined by HPLC

then the cumulative permeation quantity

steady transdermal rate and other penetration kinetic parameters were calculated. Result:Compared with Tripterygii Radix et Rhizoma cream

compatibility of Paeoniae Radix Alba and Tripterygii Radix et Rhizoma cream group could reduce cumulative penetration amounts of wilforgine and wilforine;among them

cumulative penetration amounts at 24 h of wilforgine and wilforine in cream with compatibility of Tripterygii Radix et Rhizoma and Paeoniae Radix Alba in 1:2 and 1:3 showed a significant decreasing trend;but the cumulative penetration amount of triptolide without the influence of compatibility. Conclusion:The compatibility of Tripterygii Radix et Rhizoma and Paeoniae Radix Alba can decrease the permeation of toxic components

and do not affect the permeability of triptolide

which is the main active substance of Tripterygii Radix et Rhizoma

so as to achieve the effect of reducing toxicity and increasing efficiency.