Assessment of intestinal absorption of O-glycoside flavonoid avicularin using in situ single-pass intestinal perfusion technique

For a drug to become a product it is required to elucidate its behavior in the organism, and one of the steps is to characterize the intestinal absorption, including the transport mechanisms and the transport rate of the drug. The aim of this study was to investigate the absorption mechanism of Quercetin 3-O-α-L-arabinofuranoside, avicularin, isolated from the aerial parts of Bidens sulphurea, in the rat intestine, using the in situ single-pass intestinal perfusion technique. The influence of the P-glycoprotein inhibitor aerapamil in the absorption of avicularin was studied as well. Because water absorption and secretion during perfusion may cause errors, phenolred, a non-absorbable marker, was co-perfused to correct water flux. A fast, sensitive, and specific UPLC-MS-MS method for determination of avicularin and phenolred in the intestinal samples has been developed and validated. Avicularin, phenolred and coumarin (internal standard) were extracted from the intestinal perfusion samples by solid phase extraction. The proposed method was successfully applied to the determination of AV and PR in intestinal perfusion samples and pharmacokinetics parameters were calculated.