RESUMO
OBJECTIVE To study the pharmacokinetic characters of Baihe -zhimu decoction （BZD） and its single herbs . METHODS A liquid chromatography -tandem mass spectrometry method was developed to simultaneously determine the blood concentrations of 7 effective components （neomangiferin，mangiferin，regaloside A ，regaloside Ⅰ，timosaponin B Ⅱ，timosaponin E and timosaponin A Ⅲ）in rats after oral administration of BZD extract ，single herb extract of Lilium brownii and Anemarrhena asphodeloides. The pharmacokinetic parameters were calculated . RESULTS The linear range of 7 effective components as neomangiferin were 1-1 000，1-1 000，0.1-100，0.4-400，1-1 000，0.1-100 and 0.5-500 ng/mL（all r＞0.998），respectively. The accuracy of the method ranged from 87.50% to 115.00%，and the RSDs of intra -day and inter -day precision were 0.62%-14.35%. RSDs of matrix factor were 2.68%-14.03%，and deviation of stability were within ±15%. Compared with L. brownii and A. asphodeloides，AUC0－24h，AUC0－∞ and cmax of 7 effective components in BZD were increased significantly （P＜0.05），while CL z/Fof 6 effective components （except timosaponin B Ⅱ）decreased significantly （P＜0.05）. CONCLUSIONS BZD can increase the absorption of effective ingredients in rats ，slow down their elimination and prolong their retention time ，indicating pharmacokinetic behaviors of effective components in BZD possess more advantages over those of single herbs .